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Ruthenium(II)–Arene Complexes with Glycosylated NHC-Carbene Co-Ligands: Synthesis, Hydrolytic Behavior, and Binding to Biological Molecules

Electronic Supplementary Material (ESI) for Dalton Transactions. This journal is © The Royal Society of Chemistry 2024 Supporting Information The Coordination of Alkali-Metal Nickelates to Organic π-Systems: Synthetic, Structural and Spectroscopic Insights Andryj M. Borys,a* Luca Vedani,a Eva Heviaa* a Departement für Chemie, Biochemie und Pharmacie, Universität Bern, 3012 Bern, Switzerland Table of Contents Experimental ............................................................................................................................................4 General Considerations ........................................................................................................................4 Synthesis and Purification of PhLi .........................................................................................................4 Synthesis of Alkali-Metal Nickelates ......................................................................................................5 Synthesis of [(ttt-CDT)NiPh][Li(12-crown-4)2] (1) ...............................................................................5 Synthesis of Li2(TMEDA)2Ph2Ni(η2-CDT) (2)......................................................................................5 Synthesis of Li4(TMEDA)2(Et2O)2Ph4Ni2(µ;η2;η2-C6H4) (3) ..................................................................6 Synthesis of Li2(THF)4Ph2Ni(η2-anthracene) (4Li)..............................................................................6 Synthesis of Na2(TMEDA)2Ph2Ni(η2-anthracene) (4Na) .....................................................................7 Synthesis of K2(PMDETA)2Ph2Ni(η2-anthracene) (4K) .......................................................................8 Synthesis of Li2(THF)4Ph2Ni(η2-phenanthrene) (5Li) .........................................................................8 Synthesis of [Na2(THF)3Ph2Ni(η2-phenanthrene)]2 (5Na) ...................................................................9 Synthesis of [K2(THF)1Ph2Ni(η2-phenanthrene)]∞ (5K) .....................................................................10 Synthesis of [Li(THF)2Ph2Ni(η3-perylene)][Li(THF)4] (6Li) ................................................................10 Synthesis of [Li(THF)2Ph2Ni(η2-coronene)][Li(THF)4] (7Li)...............................................................11 Synthesis of K2(DME)4Ph2Ni(η2-coronene) (7K) ..............................................................................11 Synthesis of [Li2(THF)3Ph2Ni(η2-Ph2CO)]2 (8Li) ...............................................................................12 Synthesis of [K2(DME)3Ph2Ni(η2-Ph2CO)]2 (8K) ...............................................................................12 Synthesis of Li2(THF)5Ph2Ni(η2-PhCH=NPh) (9Li) ...........................................................................13 Synthesis of [Li2(THF)3Ph2Ni(η2-Ph2CHCN)]2 (10Li) ........................................................................14 Synthesis of Li(THF)3(PPh3)2(CO)3Ni2(µ-PPh2) (11Li)......................................................................14 Variable Temperature NMR Spectroscopy .............................................................................................15 [Li(THF)2Ph2Ni(η2-coronene)][Li(THF)4] (7Li) ......................................................................................15 DOSY NMR Spectroscopy......................................................................................................................16 [Na2(THF)3Ph2Ni(η2-phenanthrene)]2 (5Na) .........................................................................................16 [K2(THF)1Ph2Ni(η2-phenanthrene)]∞ (5K).............................................................................................17 EPR Spectroscopy .................................................................................................................................18 X-Ray Crystallography............................................................................................................................20 Solid-State Structure of [(ttt-CDT)NiPh][Li(12-crown-4)2] (1) ...............................................................28 Solid-State Structure of Li4(TMEDA)2(Et2O)2Ph4Ni2(µ;η2;η2-C6H4) (3) ..................................................28 Solid-State Structure of Li2(THF)4Ph2Ni(η2-anthracene) (4Li) ..............................................................29 Solid-State Structure of Na2(TMEDA)2Ph2Ni(η2-anthracene) (4Na) .....................................................29 Solid-State Structure of K2(PMDETA)2Ph2Ni(η2-anthracene) (4K) .......................................................30 Solid-State Structure of Li2(THF)4Ph2Ni(η2-phenanthrene) (5Li) ..........................................................30 Solid-State Structure of [Na2(THF)3Ph2Ni(η2-phenanthrene)]2 (5Na) ...................................................31 Solid-State Structure of [K2(THF)1Ph2Ni(η2-phenanthrene)]∞ (5K) .......................................................31 Solid-State Structure of [Li(THF)2Ph2Ni(η3-perylene)][Li(THF)4] (6Li) ..................................................32 Solid-State Structure of [perylene][K(DME)4] .......................................................................................32 Solid-State Structure of [Li(THF)2Ph2Ni(η2-coronene)][Li(THF)4] (7Li) .................................................33 Solid-State Structure of K2(DME)4Ph2Ni(η2-coronene) (7K) .................................................................34 Solid-State Structure of [Li2(THF)3Ph2Ni(η2-Ph2CO)]2 (8Li) .................................................................34 Solid-State Structure of [K2(DME)3Ph2Ni(η2-Ph2CO)]2 (8K) .................................................................35 Solid-State Structure of Li2(THF)5Ph2Ni(η2-PhCH=NPh) (9Li) .............................................................36 Solid-State Structure of [Li2(THF)3Ph2Ni(η2-Ph2CHCN)]2 (10Li) ..........................................................36 Solid-State Structure of Li(THF)3(PPh3)2(CO)3Ni2(µ-PPh2) (11Li) ........................................................37 NMR Spectra of Reported Compounds ..................................................................................................38 Reference Spectra ..............................................................................................................................61 In Situ Synthesis and Characterisation of Imine Addition Product, Ph2CHN(Li)Ph ...........................64 In Situ Synthesis and Characterisation of Lithiated Diphenylketenimine, Ph2C=C=N–Li ..................66 References .............................................................................................................................................68 Experimental General Considerations All manipulations were carried out under an inert atmosphere of argon using standard Schlenk line or glovebox techniques (MBraun UNILab Pro ECO, <0.1 ppm H2O and O2).1,2 All manipulations, except for the synthesis of PhLi or Ni(ttt-CDT), must avoid the use of Teflon-coated stir bars or cannulae, and glasscoated stir bars should be used. THF was dried and distilled from Na/benzophenone and stored over 4 Å molecular sieves, then further dried and vacuum distilled over NaK2.8 or a sodium mirror. Hexane, pentane, Et2O and toluene were pre-dried using a MBraun MBSPS 5, then further dried and vacuum distilled over NaK2.8 or a sodium mirror, and stored over 4 Å molecular sieves. THF-d8 and C6D6 were dried and vacuum distilled over NaK2.8 and stored over 4 Å molecular sieves. TMEDA and PMDETA were distilled over CaH2 and stored over 4 Å molecular sieves. DME was dried and distilled from Na/benzophenone and stored over 4 Å molecular sieves.12-crown-4 was degassed by three freeze-pump-thaw cycles and stored over 4 Å molecular sieves. Ni(ttt-CDT) was prepared according to literature procedures and purified by vacuum sublimation.3 Anthracene and phenanthrene were dried and sublimed in vacuo prior to use. All other reagents were used as supplied and dried in vacuo prior to use. Glovebox filtrations to separate insoluble solids were performed using 0.2 µm polypropylene (PP) syringe filters. Low temperature glovebox reactions were maintained using custom-made aluminium cooling blocks that were stored in the glovebox freezer (-30 °C) prior to use. NMR spectra were recorded on Bruker Avance III HD 300 MHz or 400 MHz spectrometers at 300 K unless otherwise specified. 1H NMR spectra were referenced internally to the corresponding residual protio solvent peaks. CHN elemental microanalyses were performed on a Flash 2000 Organic Elemental Analyser (Thermo Scientific). Samples were prepared and crimped in tin capsules in an argon filled glovebox. Analyses were performed in triplicate, and reference standards (e.g. nicotinamide) were measured prior to use as controls. EPR spectra were recorded at room temperature in 1.5 mm inset capillaries on a Bruker EMXnano instrument. Synthesis and Purification of PhLi Iodobenzene (10.7 mL, 96 mmol) was dissolved in hexane (200 mL) and cooled to -78 °C. nBuLi (1.6 M, 60 mL, 96 mmol) was added dropwise and the reaction was maintained at -78 °C for 30 minutes then warmed to room temperature and stirred for 2 hours giving a thick colourless suspension. Additional hexane (2 × 100 mL) was added to loosen the suspension, and the solids were collected on a filter frit, then washed with hexane (2 × 50 mL), and dried in vacuo. Yield – 7.85 g (97%). 2.52 g of PhLi was suspended in hexane (40 mL) and Et2O (5 mL) was added. The cloudy solution was filtered to remove insoluble impurities and the filtrate was stored at -40 °C for 3 hours to give colourless crystals of [PhLi(Et2O)]4. The supernatant was removed via filter cannula and the crystals were thoroughly dried in vacuo for several hours to remove coordinated Et2O. Yield – 2.15 g (84% recovery). 1H NMR spectroscopy indicates 2% residual Et2O (MW = 85.52 g mol-1). H NMR (300.1 MHz, THF-d8): δ 7.92 (m, 2H, o-CH), 6.85 (m, 2H, m-CH), 6.75 (m, 1H, p-CH). 1 Li NMR (116.6 MHz, THF-d8): δ 1.56 (s). 7 Analytical data in accordance with the literature.4 Synthesis of Alkali-Metal Nickelates Synthesis of [(ttt-CDT)NiPh][Li(12-crown-4)2] (1) Ni(ttt-CDT) (22.1 mg, 0.1 mmol) was dissolved in pre-cooled THF (0.5 mL) and cooled to -30 °C. PhLi (8.6 mg, 0.1 mmol) was slowly added as a pre-cooled solution in THF (0.5 mL) resulting in a colour change from red to yellow. After stirring for 1 minute at -30 °C, 12-crown-4 (40 µL, 0.25 mmol) was added and the solution was stirred for an additional minute before being filtered and stored at -30 °C for crystallisation via pentane vapour diffusion. After 48 hours, the supernatant was decanted from the yellow crystals, which were washed with cold pentane (2 × 0.5 mL) and dried under argon. Yield – 39 mg (59%). H NMR (400.1 MHz, THF-d8, -20 °C): δ 7.72 (br, 2H, Ph-o-CH), 6.41 (br, 2H, Ph-m-CH), 6.20 (br, 1H, Ph- 1 p-CH), 3.39(s, 32H, 12-crown-4-CH2), 3.23 (br, 6H, CDT-CH2), 1.74 (br, 6H, CDT-CH2), 1.40 (br, 3H, CDTCH), 1.00 (br, 3H, CH). Li NMR (155.5 MHz, THF-d8, -20 °C): δ -0.69 (s). 7 C{1H} NMR (100.6 MHz, THF-d8, -20 °C): δ 195.3 (Ph-ipso-C), 144.4 (Ph-o-CH), 124.6 (Ph-m-CH), 117.5 13 (Ph-p-CH), 87.2 (CDT-CH), 82.4 (CDT-CH), 69.2 (12-crown-4-CH2), 40.5 (CDT-CH2), 38.7 (CDT-CH2). Elemental Analysis: Calculated for C34H55LiNiO8: C, 62.12; H, 8.43. Found: C, 62.16; H, 8.43. Synthesis of Li2(TMEDA)2Ph2Ni(η2-CDT) (2) Ni(ttt-CDT) (44.2 mg, 0.2 mmol) was dissolved in Et2O (0.5 mL) and cooled to -30 °C. PhLi (34.2 mg, 0.4 mmol) was slowly added as a chilled solution in Et2O (0.5 mL) followed by TMEDA (75 µL, 0.5 mmol). The orange/red solution was warmed to room temperature and stirred for 15 minutes, then filtered and stored at -30 °C for crystallisation. After 4 hours, the orange/brown solids were decanted from the supernatant, washed with cold pentane (2 × 0.5 mL) and dried under argon. Yield – 20 mg (16%). H NMR (300.1 MHz, THF-d8): δ 7.91 (d, J = 6.7 Hz, 4H, Ph-o-CH), 6.71 (t, J = 7.1 Hz, 4H, Ph-m-CH), 1 6.49 (t, J = 6.9 Hz, 2H, Ph-p-CH), 5.35–5.19 (m, 2H, CDT-CH), 5.12–4.96 (m, 2H, CDT-CH), 2.30 (s, 8H, TMEDA-CH2), 2.14 (s, 24H, TMEDA-CH3), 2.14–1.98 (m, 4H + 2H, CDT-CH2), 1.96–1.74 (m, 4H, CDTCH2), 1.06–0.90 (m, 2H, CDT-CH2), 0.16 (d, J = 6.6 Hz, 2H, CDT-CH-coordinated). Li NMR (116.6 MHz, THF-d8): δ 0.38 (s). 7 C{1H} NMR (75.5 MHz, THF-d8): δ 191.9 (Ph-ipso-C), 142.5 (Ph-o-CH), 137.0 (CDT-CH), 127.3 (CDT- 13 CH), 125.9 (Ph-m-CH), 119.2 (Ph-p-CH), 59.1 (TMEDA-CH2), 46.8 (CDT-CH-coordinated), 46.4 (TMEDACH3), 37.3 (CDT-CH2), 36.8 (CDT-CH2), 32.6 (CDT-CH2). Elemental Analysis: Calculated for C36H60Li2N4Ni: C, 69.58; H, 9.73; N, 9.02. Found: C, 68.97; H, 9.91; N, 8.87. Synthesis of Li4(TMEDA)2(Et2O)2Ph4Ni2(µ;η2;η2-C6H4) (3) Ni(ttt-CDT) (44.2 mg, 0.2 mmol) was dissolved in Et2O (1 mL) and PhLi (43 mg, 0.5 mmol) was added followed by TMEDA (300 µL, 2.0 mmol). The reaction was stirred at room temperature for 3 days giving a deep red solution which was filtered and stored at -30 °C for crystallisation via pentane vapour diffusion. After 1 week, the supernatant was decanted from the dark red crystals, which were washed with cold pentane (2 × 0.5 mL) and dried under argon. Yield – 30 mg (33%). H NMR (300.1 MHz, THF-d8): δ 8.12 (d, J = 6.0 Hz, 8H, Ph-o-CH), 6.71–6.63 (m, 10H, Ph-m-CH + H3), 1 6.48 (tt, J = 7.2, 1.6 Hz, 4H, Ph-p-CH), 5.77 (dd, J = 5.5, 2.5 Hz, 2H, H2), 3.39 (q, Et2O-CH2), 2.31 (s, 8H, TMEDA-CH2), 2.15 (s, 24H, TMEDA-CH3), 1.12 (t, Et2O-CH3). Li NMR (116.1 MHz, THF-d8): δ 0.50 (vbr), -0.24 (vbr). 7 C{1H} NMR (75.5 MHz, THF-d8): δ 185.6 (Ph-ipso-C), 144.1 (Ph-o-CH), 126.0 (Ph-m-C), 125.2 (C3), 13 120.6 (Ph-p-CH), 115.9 (C2), 71.8 (br, C1), 66.5 (Et2O-CH2), 59.1 (TMEDA-CH2), 46.4 (TMEDA-CH3), 15.8 (Et2O-CH3). Elemental Analysis: Calculated for C50H76Li4N4Ni2O2: C, 65.97; H, 8.42; N, 6.15. Found: C, 65.65; H, 8.26; N, 6.04. Synthesis of Li2(THF)4Ph2Ni(η2-anthracene) (4Li) Ni(ttt-CDT) (22.1 mg, 0.1 mmol) was dissolved in Et2O (1 mL) and cooled to -30 °C. PhLi (17.1 mg, 0.2 mmol) was added and the solution was warmed to room temperature, stirred for 2-3 minutes, then recooled to -30 °C. Anthracene (17.8 mg, 0.1 mmol) was added followed by THF (0.1 mL) and the dark red reaction mixture was stirred at -30 °C for 5 minutes, then filtered and stored at -30 °C for crystallisation via pentane vapour diffusion. After 72 hours, the supernatant was decanted from the dark red/black crystals, which were washed with cold pentane (2 × 0.5 mL) and dried under argon. Yield – 36 mg (52%). H NMR (300.1 MHz, THF-d8): δ 8.00 (d, J = 6.7 Hz, 2H, Ph-o-CH), 7.44 (d, J = 6.7 Hz, 2H, Ph-o-CH), 1 7.00 (m, 2H, H6), 6.69–6.59 (m, 4H, Ph-m-CH + H7), 6.59–6.51 (m, 2H, Ph-m-CH), 6.49–6.37 (m, 4H, Php-CH + H4), 4.44 (br, 4H, H1/2), 3.62 (THF), 1.78 (THF). Li NMR (116.6 MHz, THF-d8): δ 0.26 (br). 7 C{1H} NMR (75.5 MHz, THF-d8): δ 189.8 (ipso-C), 184.5 (ipso-C), 143.1 (C3), 142.1 (o-CH), 140.7 (o- 13 CH), 134.6 (C5), 125.1 (m-CH), 124.3 (m-CH), 124.1 (C6), 120.3 (C7), 119.4 (p-CH), 119.3 (p-CH), 113.5 (C4), 90.3 (C2), 73.8 (C1). Elemental Analysis: Calculated for C42H52Li2NiO4: C, 72.75; H, 7.56. Found: C, 72.68; H, 7.73. Synthesis of Na2(TMEDA)2Ph2Ni(η2-anthracene) (4Na) Ni(ttt-CDT) (22.1 mg, 0.1 mmol) was dissolved in Et2O (1 mL) and cooled to -30 °C. PhLi (17.1 mg, 0.2 mmol) was added and the solution was warmed to room temperature, stirred for 2-3 minutes, then recooled to -30 °C. Anthracene (17.8 mg, 0.1 mmol) was added followed by toluene (1 mL), NaOtBu (24 mg, 0.25 mmol) and TMEDA (90 µL, 0.6 mmol) and the dark green reaction mixture was stirred at -30 °C for 5 minutes, then filtered and stored at -30 °C for crystallisation via pentane vapour diffusion. After 72 hours, the supernatant was decanted from the dark green/black crystals, which were washed with cold pentane (2 × 0.5 mL) and dried under argon. Yield – 28 mg (42%). H NMR (300.1 MHz, THF-d8): δ 7.60 (m, 4H, Ph-o-CH), (m, 4H, Ph-m-CH), 6.87 (dd, J = 3.3, 2.6 Hz, 2H, 1 H6), 6.70–6.62 (m, 4H, Ph-m-CH), 6.60–6.50 (m, 4H, Ph-p-CH + H7), 6.35 (s, 2H, H4), 4.58 (dd, J = 2.8, 2.3 Hz, 2H, H2), 4.42 (dd, J = 2.8, 2.3 Hz, 2H, H1), 2.30 (s, 8H, TMEDA-CH2), 2.15 (s, 24H, TMEDA-CH3). C{1H} NMR (75.5 MHz, THF-d8): δ 182.3 (Ph-ipso-C), 175.4 (Ph-ipso-C), 143.78 (C3), 142.8 (Ph-o-CH), 13 142.2 (Ph-o-CH), 134.6 (C5), 126.3 (Ph-m-CH), 126.0 (Ph-m-CH), 123.9 (C6), 120.8 (C7), 119.9 (Ph-pCH), 109.7 (C4), 86.5 (C2), 72.2 (C1), 59.1 (TMEDA-CH2), 46.4 (TMEDA-CH3). Elemental Analysis: Calculated for C38H52N4Na2Ni: C, 68.17; H, 7.83; N, 8.37. Found: C, 66.6; H, 7.67; N, 7.66. N.B. Crystalline samples were consistently low in carbon, hydrogen and nitrogen suggesting partial TMEDA decoordination. Synthesis of K2(PMDETA)2Ph2Ni(η2-anthracene) (4K) Ni(ttt-CDT) (22.1 mg, 0.1 mmol) was dissolved in Et2O (1 mL) and cooled to -30 °C. PhLi (17.1 mg, 0.2 mmol) was added and the solution was warmed to room temperature, stirred for 2-3 minutes, then recooled to -30 °C. Anthracene (17.8 mg, 0.1 mmol) was added followed by toluene (1 mL), KO tBu (28 mg, 0.25 mmol) and PMDETA (125 µL, 0.6 mmol) and the dark green reaction mixture was stirred at -30 °C for 5 minutes, then filtered and stored at -30 °C for crystallisation via pentane vapour diffusion. After 72 hours, the supernatant was decanted from the dark green/black crystals, which were washed with cold pentane (2 × 0.5 mL) and dried under argon. Yield – 22 mg (24%). H NMR (300.1 MHz, THF-d8): δ 7.69 (m, 4H, Ph-o-CH), 6.72 (dd, J = 3.6, 2.1 Hz, 2H, H6), 6.69–6.60 (m, 1 4H, Ph-m-CH), 6.51–6.44 (m, 2H, Ph-p-CH), 6.48 (dd, J = 3.6, 2.1 Hz, 2H, H7), 6.17 (s, 2H, H4), 4.50 (m, H2), 4.24 (m, 2H, H1), 2.41 (m, 8H, PMDETA-CH2), 2.31 (m, 8H, PMDETA-CH2), 2.19 (s, 6H, PMDETACH3), 2.15 (s, 24H, PMDETA-CH3). C{1H} NMR (75.5 MHz, THF-d8): δ 144.7 (C3), 142.5 (Ph-o-CH), 141.9 (Ph-o-CH), 134.8 (C5), 126.0 13 (Ph-m-CH), 125.5 (Ph-m-CH), 123.0 (C6), 120.3 (C7), 119.6 (Ph-p-CH), 119.0 (Ph-p-CH), 106.8 (C4), 87.1 (C2), 73.1 (C1), 59.0 (PMDETA-CH2), 57.5 (PMDETA-CH2), 46.5 (PMDETA-CH3), 43.5 (PMDETA-CH3). N.B. Due to poor solubility and limited stability at room temperature, signals for the Ph-ipso-carbons could not be observed in the 13C{1H} or 1H-13C HMBC spectra. Elemental Analysis: Calculated for C44H66K2N6Ni: C, 64.77; H, 8.15; N, 10.30. Found: C, 64.08; H, 8.01; N, 9.78. N.B. Crystalline samples were consistently low in carbon, hydrogen and nitrogen suggesting partial PMDETA decoordination. Synthesis of Li2(THF)4Ph2Ni(η2-phenanthrene) (5Li) Ni(ttt-CDT) (22.1 mg, 0.1 mmol) was dissolved in Et2O (1 mL) and cooled to -30 °C. PhLi (17.1 mg, 0.2 mmol) was added and the solution was warmed to room temperature, stirred for 2-3 minutes, then recooled to -30 °C. Phenanthrene (17.8 mg, 0.1 mmol) was added followed by THF (0.1 mL) and the dark red reaction mixture was stirred at -30 °C for 5 minutes, then filtered and stored at -30 °C for crystallisation via pentane vapour diffusion. After 72 hours, the supernatant was decanted from the dark red/brown crystals, which were washed with cold pentane (2 × 0.5 mL) and dried under argon. Yield – 38 mg (55%). H NMR (300.1 MHz, THF-d8): δ 7.50 (d, J = 6.5 Hz, 4H, Ph-o-CH), 7.38 (d, J = 7.6 Hz, 2H, H6), 6.64– 1 6.56 (m, 6H, Ph-m-CH + H5), 6.48–6.39 (m, 4H, Ph-p-CH + H4), 6.27 (d, J = 7.0 Hz, 2H, H3), 3.62 (THF), 2.78 (s, 2H, H1), 1.78 (THF). Li NMR (116.6 MHz, THF-d8): δ -0.27 (s). 7 C{1H} NMR (75.5 MHz, THF-d8): δ 189.7 (Ph-ipso-C), 145.7 (C7), 142.0 (Ph-o-CH), 129.6 (C2), 126.8 13 (C3), 126.0 (C5), 124.6 (Ph-m-CH), 121.0 (C6), 119.2 (Ph-p-CH), 116.3 (C4), 39.0 (C1). Elemental Analysis: Calculated for C42H52Li2NiO4: C, 72.75; H, 7.56. Found: C, 71.69; H, 7.57. Spectroscopically pure and crystalline samples were consistently low in carbon. Synthesis of [Na2(THF)3Ph2Ni(η2-phenanthrene)]2 (5Na) Ni(ttt-CDT) (22.1 mg, 0.1 mmol) was dissolved in Et2O (1 mL) and cooled to -30 °C. PhLi (17.1 mg, 0.2 mmol) was added and the solution was warmed to room temperature, stirred for 2-3 minutes, then recooled to -30 °C. Phenanthrene (17.8 mg, 0.1 mmol) was added followed by THF (0.1 mL) and NaOtBu (24 mg, 0.25 mmol) and the dark red reaction mixture was stirred at -30 °C for 5 minutes, then filtered and stored at -30 °C for crystallisation via pentane vapour diffusion. After 48 hours, the supernatant was decanted from the dark red/black crystals, which were washed with cold pentane (2 × 0.5 mL) and dried under argon. Yield – 41 mg (63%). H NMR (300.1 MHz, THF-d8): δ 7.53 (d, J = 6.7 Hz, 4H, Ph-o-CH), 7.37 (d, J = 7.8 Hz, 2H, H6), 6.69-6.56 1 (m, 8H, Ph-m-CH + H3 + H5), 6.53-6.41 (m, 4H, Ph-p-CH + H5), 3.62 (THF), 3.05 (s, 2H, H1), 1.78 (THF). C{1H} NMR (75.5 MHz, THF-d8): δ 187.8 (Ph-ipso-C), 146.5 (C7), 142.4 (Ph-o-CH), 129.0 (C2), 126.9 13 (C5), 125.5 (Ph-m-CH), 125.1 (C3), 121.5 (C6), 119.5 (Ph-p-CH), 116.7 (C4), 38.9 (C1). Elemental Analysis: Calculated for C38H44Na2NiO3: C, 69.85; H, 6.79. Found: C, 69.30; H, 6.82. Synthesis of [K2(THF)1Ph2Ni(η2-phenanthrene)]∞ (5K) Ni(ttt-CDT) (22.1 mg, 0.1 mmol) was dissolved in Et2O (1 mL) and cooled to -30 °C. PhLi (17.1 mg, 0.2 mmol) was added and the solution was warmed to room temperature, stirred for 2-3 minutes, then recooled to -30 °C. Phenanthrene (17.8 mg, 0.1 mmol) was added followed by THF (0.1 mL) and KO tBu (28 mg, 0.25 mmol) and the dark red reaction mixture was stirred at -30 °C for 5 minutes, then filtered and stored at -30 °C for crystallisation via pentane vapour diffusion. After 72 hours, the supernatant was decanted from the dark purple/black crystals, which were washed with cold pentane (2 × 0.5 mL) and dried under argon. Yield – 23 mg (43%). H NMR (300.1 MHz, THF-d8): δ 7.64 (dd, J = 7.5, 1.4 Hz, 4H, Ph-ortho-CH), 7.27 (d, J = 7.2 Hz, 2H, H6), 1 6.62 (m, 6H, Ph-meta-CH + H3), 6.49 (td, J = 7.9, 1.2 Hz, 2H, H5), 6.43 (tt, J = 7.2, 1.5 Hz, 2H, Ph-paraCH), 6.34 (td, J = 6.8, 1.4 Hz, 2H, H4), 3.62 (THF), 3.09 (s, 2H, H1), 1.78 (THF). C{1H} NMR (75.5 MHz, THF-d8): δ 193.7 (Ph-ipso-C), 147.6 (C7), 142.7 (Ph-ortho-CH), 128.2 (C2), 127.1 13 (C5), 125.4 (Ph-meta-CH), 124.2 (C3), 121.5 (C6), 118.5 (Ph-para-CH), 115.8 (C4), 40.5 (C1). Elemental Analysis: Calculated for C30H28K2NiO: C, 66.55; H, 5.21. Found: C, 66.25; H, 5.21. Synthesis of [Li(THF)2Ph2Ni(η3-perylene)][Li(THF)4] (6Li) Ni(ttt-CDT) (22.1 mg, 0.1 mmol) was dissolved in Et2O (1 mL) and cooled to -30 °C. PhLi (17.1 mg, 0.2 mmol) was added and the solution was warmed to room temperature, stirred for 2-3 minutes, then recooled to -30 °C. Perylene (25.2 mg, 0.1 mmol) was added followed by THF (0.5 mL) and the dark purple reaction mixture was stirred at -30 °C for 5 minutes, then filtered and stored at -30 °C for crystallisation via pentane vapour diffusion. After 72 hours, the supernatant was decanted from the dark blue/purple crystals, which were washed with cold pentane (2 × 0.5 mL) and dried under argon. Yield – 65 mg (71%). N.B. Isolated samples were contaminated with small bronze crystals identified as the perylene radical anion by EPR spectroscopy (see Figure S5) and could therefore not be isolated in pure form for suitable elemental analysis. H NMR (300.1 MHz, THF-d8): δ 7.89 (d, J = 6.9 Hz, 2H), 7.54 (d, J = 6.8 Hz, 2H), 6.80–6.65 (m, 6H), 1 6.59–6.47 (m, 4H), 6.23 (t, J = 7.4 Hz, 2H), 6.08 (d, J = 7.2 Hz, 2H), 5.84 (br, 2H), 5.65 (br, 2H), 4.60 (vbr, 2H), 3.62 (THF), 1.78 (THF). Li NMR (116.6 MHz, THF-d8): δ -0.68 (s). 7 C{1H} NMR (75.5 MHz, THF-d8): δ 178.5, 176.2, 143.0, 139.7, 129.1, 125.3, 125.2, 121.2, 114.6. Signals 13 for the coordinated perylene could not be observed in the 13C{1H}, 1H-13C HSQC or 1H-13C HMBC spectra. Synthesis of [Li(THF)2Ph2Ni(η2-coronene)][Li(THF)4] (7Li) Ni(ttt-CDT) (22.1 mg, 0.1 mmol) was dissolved in Et2O (1 mL) and cooled to -30 °C. PhLi (17.1 mg, 0.2 mmol) was added and the solution was warmed to room temperature, stirred for 2-3 minutes, then recooled to -30 °C. Coronene (30.0 mg, 0.1 mmol) was added followed by THF (1 mL) and the dark reaction mixture was stirred at -30 °C for 5 minutes, then filtered and stored at -30 °C for crystallisation via pentane vapour diffusion. After 48 hours, the supernatant was decanted from the dark black/green crystals, which were washed with cold pentane (2 × 0.5 mL) and dried under argon. Yield – 24 mg (24%). H NMR (400.1 MHz, THF-d8, -20 °C): δ 7.45 (s, 2H), 7.39 (d, J = 6.5 Hz, 4H, Ph-o-CH), 7.10 (s, 4H), 6.98 1 (d, J = 7.9 Hz, 2H), 6.59 (t, J = 7.0 Hz, 4H, Ph-m-CH), 6.41–6.32 (m, 2H + 2H, Ph-p-CH), 3.62 (THF), 3.30 (s, 2H), 1.78 (THF). Li NMR (155.5 MHz, THF-d8, -40 °C): δ 0.52 (br), 0.00 (br). 7 C{1H} NMR (100.6 MHz, THF-d8, -20 °C): δ 189.6 (Ph-ipso-C), 142.0, 140.6 (Ph-o-CH), 130.6, 128.7, 13 128.6, 128.4, 125.1, 124.5, 124.4, 124.2 (Ph-m-CH), 123.3, 119.7, 119.0 (Ph-p-CH), 42.3. Elemental Analysis: Calculated for C60H70Li2NiO6: C, 75.09; H, 7.35. Found: C, 74.91; H, 7.35. Synthesis of K2(DME)4Ph2Ni(η2-coronene) (7K) Ni(ttt-CDT) (11.0 mg, 0.05 mmol) was dissolved in Et2O (1 mL) and cooled to -30 °C. PhLi (8.6 mg, 0.1 mmol) was added and the solution was warmed to room temperature, stirred for 2-3 minutes, then recooled to -30 °C. Coronene (15.0 mg, 0.05 mmol) was added slowly as a solution/suspension in DME (1 mL), followed by KOtBu (14 mg, 0.125 mmol) and the black reaction mixture was stirred at -30 °C for 5 minutes, then filtered and stored at -30 °C for crystallisation via pentane vapour diffusion. After 72 hours, the supernatant was decanted from the dark black crystals, which were washed with cold pentane (2 × 0.5 mL) and dried under argon. Yield – 21 mg (44%). N.B. Isolated samples were found to be contaminated with the coronene radical anion by EPR spectroscopy (see Figure S8) and could therefore not be isolated in pure form for suitable elemental analysis. H NMR (300.1 MHz, THF-d8): δ 7.62 (d, J = 6.7 Hz, 4H, Ph-o-CH), 7.18 (vbr, coronene), 6.62 (t, J = 6.9 1 Hz, 4H, Ph-m-CH), 6.41 (t, J = 6.9 Hz, 2H, Ph-p-CH), 3.53 (DME-CH2), 3.35 (DME-CH3). N.B. Due to poor solubility of 7K, low temperature measurements were not possible. Synthesis of [Li2(THF)3Ph2Ni(η2-Ph2CO)]2 (8Li) Ni(ttt-CDT) (22.1 mg, 0.1 mmol) was dissolved in Et2O (1 mL) and cooled to -30 °C. PhLi (17.1 mg, 0.2 mmol) was added and the solution was warmed to room temperature, stirred for 2-3 minutes, then recooled to -30 °C. Benzophenone (18.2 mg, 0.1 mmol) was added followed by THF (0.1 mL) and the dark purple/green reaction mixture was stirred at -30 °C for 5 minutes, then filtered and stored at -30 °C for crystallisation via pentane vapour diffusion. After 72 hours, the supernatant was decanted from the dark purple crystals, which were washed with cold pentane (2 × 0.5 mL) and dried under argon. Yield – 39 mg (62%). N.B. The 1H NMR spectrum of 8Li was very broad at room temperature and whilst cooling to -20 °C does lead to improvement of resolution and sharpening of signals, the significant overlap means it is not possible to confidently assign signals (see Spectra 33–35). Elemental Analysis: Calculated for C37H44Li2NiO4: C, 71.07; H, 7.09. Found: C, 70.58; H, 7.14. Synthesis of [K2(DME)3Ph2Ni(η2-Ph2CO)]2 (8K) Ni(ttt-CDT) (22.1 mg, 0.1 mmol) was dissolved in Et2O (1 mL) and cooled to -30 °C. PhLi (17.1 mg, 0.2 mmol) was added and the solution was warmed to room temperature, stirred for 2-3 minutes, then recooled to -30 °C. Benzophenone (18.2 mg, 0.1 mmol) was added followed by DME (0.5 mL) and KOtBu (28 mg, 0.25 mmol) and the black reaction mixture was stirred at -30 °C for 5 minutes, then filtered and stored at 30 °C for crystallisation via pentane vapour diffusion. After 72 hours, the supernatant was decanted from the dark blue crystals, which were washed with cold pentane (2 × 0.5 mL) and dried under argon. Yield – 37 mg (50%). H NMR (300.1 MHz, THF-d8): δ 7.99 (d, J = 5.9 Hz, 2H, Ph-o-CH), 7.40 (d, J = 7.0 Hz, 4H, Ph2CO-o-CH), 1 7.28 (d, J = 7.0 Hz, 2H, Ph-o-CH), 6.90 (t, J = 6.9 Hz, 4H, Ph2CO-m-CH), 6.77 (t, J = 6.3 Hz, 2H, Ph2COp-CH), 6.64 (d, J = 6.9 Hz, 2H, Ph-m-CH), 6.59 (d, J = 6.7 Hz, 1H, Ph-p-CH), 6.41 (t, J = 7.0 Hz, 2H, Phm-CH), 6.29 (t, J = 7.0 Hz, 1H, Ph-o-CH), 3.43 (DME-CH2), 3.27 (DME-CH3). C{1H} NMR (75.5 MHz, THF-d8): δ 185.4 (Ph-ipso-C), 153.6 (Ph2CO-ipso-C), 143.1 (br, Ph-o-CH), 141.2 13 (Ph-o-CH), 127.9 (Ph2CO-m-CH), 125.9 (Ph2CO-p-CH), 124.8 (br, Ph2CO-o-CH), 124.5 (Ph-m-CH), 120.0 Ph-p-CH), 118.7 (Ph-m-CH), 117.7 (Ph-p-CH), 72.9 (DME-CH2), 59.1 (DME-CH3). N.B. Signals for the carbonyl carbon not observed in the 13C{1H} or 1H-13C HMBC spectra. Elemental Analysis: Calculated for C37H50K2NiO7: C, 59.76; H, 6.78. Found: C, 59.72; H, 6.60. Synthesis of Li2(THF)5Ph2Ni(η2-PhCH=NPh) (9Li) Ni(ttt-CDT) (22.1 mg, 0.1 mmol) was dissolved in Et2O (1 mL) and cooled to -30 °C. PhLi (17.1 mg, 0.2 mmol) was added and the solution was warmed to room temperature, stirred for 2-3 minutes, then recooled to -30 °C. N-benzylideneaniline (18.1 mg, 0.1 mmol) was added followed by THF (0.1 mL) and the red reaction mixture was stirred at -30 °C for 5 minutes, then filtered and stored at -30 °C for crystallisation via pentane vapour diffusion. After 72 hours, the supernatant was decanted from the bright red crystals, which were washed with cold pentane (2 × 0.5 mL) and dried under argon. Yield – 31 mg (50%). H NMR (300.1 MHz, THF-d8):  8.00 (d, J = 6.4 Hz, 2H, H2/6), 7.87 (d, J = 6.4 Hz, 2H, H2/6), 6.92–6.83 1 (m, 2H + 2H, H3/7 + H15), 6.77–6.68 (m, 2H + 2H + 2H +1H, H3/7 + H11, H12, H4/8), 6.68–6.59 (m, 2H, H16), 6.59–6.48 (m, 1H + 1H, H4/8 + H13), 6.38 (t, J = 7.1 Hz, 1H, H17), 3.81 (s, 1H, H9), 3.62 (THF), 1.77 (THF). Li NMR (116.6 MHz, THF-d8):  -0.12 (s). 7 C{1H} NMR (75.5 MHz, THF-d8):  181.8 (C1/5), 179.7 (C1/5), 161.0 (C14), 153.6 (C10), 143.7 (C2/6), 13 142.4 (C2/6), 128.6 (C15), 127.8 (C12), 126.0 (C3/7), 125.7 (C3/7), 124.8 (C11), 121.7 (C4/8), 120.9 (C16), 120.3 (C13), 119.8 (C4/8), 114.4 (C17), 67.6 (THF), 53.7 (C9), 25.5 (THF). Elemental Analysis: Calculated for C45H61Li2NNiO5: C, 70.33; H, 8.00; N, 1.82. Found: C, 70.30; H, 8.07; N, 1.74. N.B. NMR spectroscopy and elemental analysis consistent with three molecules of coordinated THF. Synthesis of [Li2(THF)3Ph2Ni(η2-Ph2CHCN)]2 (10Li) Ni(ttt-CDT) (22.1 mg, 0.1 mmol) was dissolved in Et2O (1 mL) and cooled to -30 °C. PhLi (17.1 mg, 0.2 mmol) was added and the solution was warmed to room temperature, stirred for 2-3 minutes, then recooled to -30 °C. Diphenylacetonitrile (19.3 mg, 0.1 mmol) was added slowly as a chilled solution in THF (1 mL) and the amber reaction mixture was stirred at -30 °C for 5 minutes, then filtered and stored at -30 °C for crystallisation via pentane vapour diffusion. After 48 hours, the supernatant was decanted from the bright yellow crystals, which were washed with cold pentane (2 × 0.5 mL) and dried under argon. Yield – 27 mg (42%). H NMR (400.1 MHz, THF-d8, -20 °C): δ 8.10 (d, J = 6.9 Hz, 2H), 7.89 (d, J = 6.7 Hz, 2H), 7.52–7.35 (m, 1 4H), 7.05 (m, 4H), 6.98 (m, 2H), 6.90 (br, 2H), 6.72 (br, 3H), 6.60–6.47 (m, 2H), 5.29 (br, 1H), 3.62 (THF), 1.78 (THF). Li NMR (155.5 MHz, THF-d8, -20 °C): δ 0.33 (br). 7 N.B. Due to poor solution-state stability and low solubility at low temperatures, suitable 13C{1H} NMR spectral data could not be obtained. Elemental Analysis: Calculated for C38H45Li2NNiO3: C, 71.72; H, 7.13; N, 2.20. Found: C, 71.01; H, 7.09; N, 2.09. Synthesis of Li(THF)3(PPh3)2(CO)3Ni2(µ-PPh2) (11Li) (Ph3P)2Ni(CO)2 (25.5 mg, 0.04 mmol) was dissolved in THF-d8 (0.5 mL) and PhLi (6.8 mg, 0.08 mmol) was added at room temperature resulting in a colour change from colourless to deep red. New signals were observed in the 31P NMR spectrum at δ 45.5 and 28.7 ppm which grew in intensity over the course of 2 days as the signal for the starting material (δ 32.6) disappeared. Additional signals at δ 31.5 (unidentified species) and -5.5 (Ph3P) were also observed, alongside numerous minor signals. The solution was decanted into a vial and stored at -30 °C for crystallisation via pentane vapour diffusion. After 72 hours, red crystals of 11Li suitable for X-ray diffraction were obtained. The supernatant was decanted and the solids were washed with cold pentane (0.5 mL) and dried under argon. Yield – 6 mg (26%). H NMR (300.1 MHz, THF-d8): δ 7.34 (br, 12H), 7.20–7.02 (m, 22H), 6.48 (m, 6H). 1 Li NMR (116.6 MHz, THF-d8): δ -0.62 (br). 7 P NMR (121.5 MHz, THF-d8): δ 45.7 (s, 1P), 28.7 (s, 2P). 31 Variable Temperature NMR Spectroscopy [Li(THF)2Ph2Ni(η2-coronene)][Li(THF)4] (7Li) 15 mg of [Li(THF)2Ph2Ni(η2-coronene)][Li(THF)4] (7Li) was dissolved in THF-d8 (0.5 mL) and analysed by 1 H and 7Li NMR spectroscopy at +20 °C, +10 °C, 0 °C, -10 °C, -20 °C, -30 °C and -40 °C (Figures S1–2). Figure S1: Stacked 1H NMR spectra at variable temperatures for [Li(THF)2Ph2Ni(η2-coronene)][Li(THF)4] (7Li). Figure S2: Stacked 7Li NMR spectra at variable temperatures for [Li(THF)2Ph2Ni(η2-coronene)][Li(THF)4] (7Li). DOSY NMR Spectroscopy Estimated molecular weights (MW) were calculated from the diffusion coefficients established from the 1H DOSY NMR spectrum using Stalke’s external calibration curve (ECC) method5–7 and using tetramethylsilane as an internal standard. Samples were prepared by dissolving 0.0075 mmol each of complex and internal standard in 500 µL of THF-d8 to give a concentration of 15 mM. [Na2(THF)3Ph2Ni(η2-phenanthrene)]2 (5Na) Predicted molecular weight for Na2(THF)4Ph2Ni(η2-phenanthrene) = 725.55 g mol-1. Estimated molecular weights determined from diffusion coefficients = 683 g mol-1 (Merge), 6% difference; 626 g mol-1 (DSE), 16% difference (Figure S3). Figure S3: 1H DOSY NMR spectrum of [Na2(THF)3Ph2Ni(η2-phenanthrene)]2 (5Na) in THF-d8. [K2(THF)1Ph2Ni(η2-phenanthrene)]∞ (5K) Predicted molecular weight for K2(THF)4Ph2Ni(η2-phenanthrene) = 757.76 g mol-1. Estimated molecular weights determined from diffusion coefficients = 713 g mol-1 (Merge), 6% difference; 652 g mol-1 (DSE), 16% difference (Figure S4). Figure S4: 1H DOSY NMR spectrum of [K2(THF)1Ph2Ni(η2-phenanthrene)]∞ (5K) in THF-d8. EPR Spectroscopy Samples for EPR spectroscopy were prepared by dissolving approximately 1 mg of compound in 1 mL of THF and transferring 50 µL to a 1.5 mm inset capillary that was placed within a quartz EPR tube and sealed. Figure S5: EPR spectrum of crystalline [Li(THF)2Ph2Ni(η3-perylene)][Li(THF)4] (6Li) contaminated with the perylene radical anion. Figure S6: EPR spectrum of the solids isolated during the attempted synthesis of Na2(solv)nPh2Ni(perylene). Figure S7: EPR spectrum of isolated [perylene][K(DME)4] during the attempted synthesis of K2(solv)nPh2Ni(perylene). Figure S8: EPR spectrum of crystalline K2(DME)4Ph2Ni(η2-coronene) (7K) contaminated with the coronene radical anion. X-Ray Crystallography The crystal structures of all novel compounds have been deposited into the Cambridge Crystallographic Data Centre (CCDC) and have been assigned the following numbers: 2326086–2326102. Selected crystallographic and refinement parameters are presented below (Tables S1–5). In all cases, crystals immersed in an inert parabar oil were mounted at low temperatures and transferred into the nitrogen stream (100 or 173 K). Perfluorinated oils must be avoided for the alkali-metal nickelates. All measurements were made on a RIGAKU Synergy S area-detector diffractometer using mirror optics monochromated Cu Kα radiation (λ = 1.54184 Å) or on a RIGAKU XtaLAB Synergy R, HyPix-Arc 100 areadetector diffractometer using mirror optics monochromated Mo Kα radiation (λ = 0.71073 Å). Data reduction was performed using the CrysAlisPro program.8 The intensities were corrected for Lorentz and polarization effects, and an absorption correction based on the Gaussian method using SCALE3 ABSPACK in CrysAlisPro was applied. The structure was solved by direct methods or intrinsic phasing using SHELXT,9 which revealed the positions of all non-hydrogen atoms of the compounds. All nonhydrogen atoms were refined anisotropically. H-atoms were assigned in geometrically calculated positions and refined using a riding model where each H-atom was assigned a fixed isotropic displacement parameter with a value equal to 1.2Ueq of its parent atom (1.5Ueq for methyl groups). Refinement of the structure was carried out on F2 using full-matrix least-squares procedures, which minimized the function Σw(Fo2 – Fc2)2. The weighting scheme was based on counting statistics and included a factor to downweight the intense reflections. All calculations were performed using the SHELXL-2014/7 program10 in OLEX2.11 For [(ttt-CDT)NiPh][Li(12-crown-4)2] (1), a disorder model was used for parts of the ttt-CDT ligand and 12-crown-4 where the occupancies of each disorder component was refined through the use of a free variable. The sum of equivalent components was constrained to 1, i.e. 100%. For Li4(TMEDA)2(Et2O)2Ph4Ni2(µ;η2;η2-C6H4) (3), a disorder model was used for parts of the coordinated Et2O and TMEDA where the occupancies of each disorder component was refined through the use of a free variable. The sum of equivalent components was constrained to 1, i.e. 100%. For Li2(THF)4Ph2Ni(η2-anthracene) (4Li), a disorder model was used for the parts of the coordinated THF where the occupancies of each disorder component were refined with the use of a free variable. The sum of equivalent components was constraint to 1, i.e. 100%. For Na2(TMEDA)2Ph2Ni(η2-anthracene) (4Na), a disorder model was used for the parts of the coordinated TMEDA where the occupancies of each disorder component was refined through the use of a free variable. The sum of equivalent components was constrained to 1, i.e. 100%. For K2(PMDETA)2Ph2Ni(η2-anthracene) (4K), a disorder model was used for several parts of the structure where the occupancies of each disorder component was refined through the use of a free variable. The sum of equivalent components was constrained to 1, i.e. 100%. For Li2(THF)4Ph2Ni(η2-phenanthrene) (5Li), a disorder model was used for parts of the coordinated THF where the occupancies of each disorder component was refined through the use of a free variable. The sum of equivalent components was constrained to 1, i.e. 100%. For [Na2(THF)3Ph2Ni(η2-phenanthrene)]2 (5Na), a disorder model was used for parts of coordinated THF where the occupancies of each disorder component was refined through the use of a free variable. The sum of equivalent components was constrained to 1, i.e. 100%. Areas containing disordered solvents were found where a satisfactory solvent model could not be achieved, therefore, a solvent mask was used to include the contribution of electron density found in void areas into the calculated structure factor. For [K2(THF)1Ph2Ni(η2-phenanthrene)]∞ (5K), twinning could be detected where the second and third twin components corresponded to a rotation of -179.9272 degrees around [-0.00 -0.00 1.00] (reciprocal space), or [0.11 0.00 0.99] (direct space) for twin component 2 and -162.9797 degrees around [-0.11 -0.01 0.99] (reciprocal space), or [-0.20 -0.05 0.98] (direct space) for twin component 3. The refinement was performed against the reflection file containing detwinned data of all 3 components on a hkl 5 format. The final refined volume fractional contribution of twins 2 and 3 were 0.4870(9) and 0.02401(17) respectively. For [Li(THF)2Ph2Ni(η3-perylene)][Li(THF)4] (6Li), a disorder model was used for coordinated THF molecules where the occupancies of each disorder component was refined through the use of a free variable. The sum of equivalent components was constrained to 1, i.e. 100%. For [Li(THF)2Ph2Ni(η2-coronene)][Li(THF)4] (7Li), a disorder model was used for coordinated THF molecules where the occupancies of each disorder component was refined through the use of a free variable. The sum of equivalent components was constrained to 1, i.e. 100%. For [Li2(THF)3Ph2Ni(η2-Ph2CO)]2 (8Li), a disorder model was used for parts of the coordinated THF where the occupancies of each disorder component was refined through the use of a free variable. The sum of equivalent components was constrained to 1, i.e. 100%. Areas containing disordered solvents were found where a satisfactory solvent model could not be achieved, therefore, a solvent mask was used to include the contribution of electron density found in void areas into the calculated structure factor. For [K2(DME)3Ph2Ni(η2-Ph2CO)]2 (8K), A disorder model was used for parts of the coordinated DME where the occupancies of each disorder component was refined through the use of a free variable. The sum of equivalent components was constrained to 1, i.e. 100%. Areas containing disordered solvents were found where a satisfactory solvent model could not be achieved, therefore, a solvent mask was used to include the contribution of electron density found in void areas into the calculated structure factor. For [Li2(THF)3Ph2Ni(η2-Ph2CHCN)]2 (10Li), a disorder model was used for parts of the coordinated THF where the occupancies of each disorder component was refined through the use of a free variable. The sum of equivalent components was constrained to 1, i.e. 100%. Areas containing disordered solvents were found where a satisfactory solvent model could not be achieved, therefore, a solvent mask was used to include the contribution of electron density found in void areas into the calculated structure factor. For Li(THF)3(PPh3)2(CO)3Ni2(µ-PPh2) (11Li), a disorder model was used for parts of the coordinated THF where the occupancies of each disorder component was refined through the use of a free variable. The sum of equivalent components was constrained to 1, i.e. 100%. Areas containing disordered solvents were found where a satisfactory solvent model could not be achieved, therefore, a solvent mask was used to include the contribution of electron density found in void areas into the calculated structure factor. Identification code CCDC Number Empirical formula Formula weight Temperature/K Crystal system Space group a/Å b/Å c/Å α/° β/° γ/° Volume/Å3 Z 1 2326086 C34H55LiNiO8 657.43 100.01(10) monoclinic P21/n 15.15520(10) 10.28020(10) 21.0871(2) 90 93.3440(10) 90 3279.74(5) 4 3 2326087 C50H76Li4N4Ni2O2 910.32 173.00(10) monoclinic P21/n 10.94240(10) 20.8208(2) 22.7000(2) 90 95.7330(10) 90 5145.86(8) 4 4Li 2326088 C42H52Li2NiO4 693.42 173.00(10) monoclinic C2/c 23.83845(18) 10.06099(9) 31.2245(3) 90 92.8991(8) 90 7479.25(11) 8 4Na 2326089 C38H52N4Na2Ni 669.52 100.00(10) monoclinic P21/n 10.5871(2) 22.0003(3) 16.2275(2) 90 94.8440(10) 90 3766.20(10) 4 ρcalcg/cm3 1.331 1.175 1.232 1.181 μ/mm-1 F(000) 0.641 1416 0.173 × 0.107 × 0.051 Mo Kα (λ = 0.71073) 0.771 1952 Mo Kα (λ = 0.71073) 1.048 2960 0.291 × 0.062 × 0.041 Cu Kα (λ = 1.54184) 0.568 1432 0.266 × 0.093 × 0.069 Mo Kα (λ = 0.71073) 4.41 to 60.162 4.104 to 60.068 5.668 to 148.956 4.282 to 61.016 Index ranges -21 ≤ h ≤ 21, -14 ≤ k ≤ 14, -29 ≤ l ≤ 29 -15 ≤ h ≤ 15, -29 ≤ k ≤ 29, -31 ≤ l ≤ 31 -29 ≤ h ≤ 29, -12 ≤ k ≤ 12, -39 ≤ l ≤ 39 -15 ≤ h ≤ 15, -31 ≤ k ≤ 31, -23 ≤ l ≤ 23 Reflections collected 191061 154783 75114 114953 Independent reflections 9636 [Rint = 0.0343, Rsigma = 0.0129] 15039 [Rint = 0.0334, Rsigma = 0.0203] 7639 [Rint = 0.0328, Rsigma = 0.0179] 11482 [Rint = 0.0436, Rsigma = 0.0275] 9636/279/561 15039/245/717 7639/172/548 11482/100/486 Crystal size/mm3 Radiation 2Θ range for data collection/° 0.16 × 0.123 × 0.05 Data/restraints/para meters Goodness-of-fit on F2 Final R indexes [I>=2σ (I)] 1.07 1.027 1.064 1.023 R1 = 0.0319, wR2 = 0.0778 R1 = 0.0307, wR2 = 0.0764 R1 = 0.0412, wR2 = 0.1189 R1 = 0.0429, wR2 = 0.0962 Final R indexes [all data] R1 = 0.0360, wR2 = 0.0794 R1 = 0.0419, wR2 = 0.0809 R1 = 0.0498, wR2 = 0.1260 R1 = 0.0672, wR2 = 0.1051 Largest diff. peak/hole / e Å-3 0.46/-0.37 0.30/-0.24 0.45/-0.33 0.44/-0.31 Table S1: Crystal data and structure refinement details for compounds 1, 3, 4Li and 4Na. Identification code CCDC Number 4K 2326090 5Li 2326091 5Na 2326092 5K 2326093 Empirical formula C44H66K2N6Ni C42H52Li2NiO4 C76H88Na4Ni2O6 C30H28K2NiO Formula weight 815.93 693.42 1306.84 541.43 Temperature/K 100.00(10) 173.00(10) 100.01(10) 173.01(10) Crystal system monoclinic monoclinic triclinic monoclinic Space group P21/n P21/n P-1 P21/c a/Å 19.97570(10) 16.7487(2) 12.22970(10) 12.46834(19) b/Å 11.46590(10) 12.4289(2) 13.7829(2) 9.88563(16) c/Å 21.46230(10) 18.2015(3) 21.3400(2) 20.5241(3) α/° 90 90 106.7570(10) 90 β/° 112.3960(10) 101.5340(10) 99.6030(10) 93.8253(14) γ/° 90 90 92.9580(10) 90 Volume/Å3 4544.93(6) 3712.45(10) 3377.08(7) 2524.11(7) Z 4 4 2 4 ρcalcg/cm3 1.192 1.241 1.285 1.425 μ/mm-1 2.517 0.562 0.635 1.12 F(000) 1752 0.215 × 0.172 × 0.097 Cu Kα (λ = 1.54184) 1480 0.176 × 0.134 × 0.071 Mo Kα (λ = 0.71073) 1384 Mo Kα (λ = 0.71073) 1128 0.178 × 0.144 × 0.110 Mo Kα (λ = 0.71073) 5.146 to 149.002 4.11 to 60.06 4.19 to 61.016 4.576 to 61.044 Index ranges -24 ≤ h ≤ 24, -14 ≤ k ≤ 13, -26 ≤ l ≤ 26 -23 ≤ h ≤ 23, -17 ≤ k ≤ 17, -25 ≤ l ≤ 25 -17 ≤ h ≤ 17, -19 ≤ k ≤ 19, -30 ≤ l ≤ 30 -17 ≤ h ≤ 17, -14 ≤ k ≤ 14, -29 ≤ l ≤ 29 Reflections collected 102150 108687 204216 23178 Independent reflections 9294 [Rint = 0.0240, Rsigma = 0.0125] 10860 [Rint = 0.0355, Rsigma = 0.0199] 20582 [Rint = 0.0484, Rsigma = 0.0307] 23178 [Rint = ?, Rsigma = 0.0390] 9294/1134/735 10860/136/495 20582/202/893 23178/0/309 Crystal size/mm3 Radiation 2Θ range for data collection/° 0.254 × 0.16 × 0.08 Data/restraints/para meters Goodness-of-fit on F2 Final R indexes [I>=2σ (I)] 1.086 1.029 1.048 1.163 R1 = 0.0557, wR2 = 0.1471 R1 = 0.0377, wR2 = 0.0971 R1 = 0.0610, wR2 = 0.1613 R1 = 0.0398, wR2 = 0.1211 Final R indexes [all data] R1 = 0.0583, wR2 = 0.1494 R1 = 0.0463, wR2 = 0.1012 R1 = 0.0884, wR2 = 0.1769 R1 = 0.0631, wR2 = 0.1279 Largest diff. peak/hole / e Å-3 0.65/-0.63 0.45/-0.33 1.34/-0.61 1.21/-1.42 Table S2: Crystal data and structure refinement details for compounds 4K, 5Li, 5Na and 5K. Identification code CCDC Number Empirical formula Formula weight Temperature/K Crystal system Space group a/Å b/Å c/Å α/° β/° γ/° Volume/Å3 Z 6Li 2326094 C56H69Li2NiO6 910.7 173.00(10) monoclinic P21/c 17.8080(4) 13.0662(2) 22.5123(4) 90 111.093(2) 90 4887.25(17) 4 [perylene][K(DME)4] 2326095 C36H52KO8 651.87 100.01(10) monoclinic C2/c 23.11620(10) 13.75360(10) 11.45110(10) 90 96.5740(10) 90 3616.72(4) 4 7Li 2326096 C60H70Li2NiO6 959.75 173.01(10) orthorhombic Pbca 13.7527(2) 21.6279(4) 34.0256(5) 90 90 90 10120.6(3) 8 7K 2326097 C52H62K2NiO8 951.92 173.00(10) orthorhombic Pca21 18.7188(3) 26.1144(5) 19.8447(3) 90 90 90 9700.7(3) 8 ρcalcg/cm3 1.238 1.197 1.26 1.304 μ/mm-1 0.447 1948 0.528 × 0.451 × 0.298 Mo Kα (λ = 0.71073) 1.67 1404 0.169 × 0.126 × 0.109 Cu Kα (λ = 1.54184) 0.435 4096 Mo Kα (λ = 0.71073) 2.532 4032 0.173 × 0.114 × 0.063 Cu Kα (λ = 1.54184) 4.786 to 61.014 7.492 to 148.994 4.248 to 61.016 7.322 to 148.98 Index ranges -25 ≤ h ≤ 25, -18 ≤ k ≤ 18, -32 ≤ l ≤ 32 -23 ≤ h ≤ 28, -17 ≤ k ≤ 17, -14 ≤ l ≤ 14 -19 ≤ h ≤ 19, -30 ≤ k ≤ 30, -46 ≤ l ≤ 48 -23 ≤ h ≤ 22, -31 ≤ k ≤ 32, -24 ≤ l ≤ 20 Reflections collected 145032 36959 242758 87034 Independent reflections 14918 [Rint = 0.0386, Rsigma = 0.0226] 3694 [Rint = 0.0296, Rsigma = 0.0148] 15457 [Rint = 0.0536, Rsigma = 0.0282] 17300 [Rint = 0.0773, Rsigma = 0.0557] 14918/198/699 3694/0/308 15457/110/708 17300/7/1168 F(000) Crystal size/mm3 Radiation 2Θ range for data collection/° 0.277 × 0.1 × 0.067 Data/restraints/para meters Goodness-of-fit on F2 Final R indexes [I>=2σ (I)] 1.031 1.06 1.034 1.026 R1 = 0.0497, wR2 = 0.1336 R1 = 0.0261, wR2 = 0.0714 R1 = 0.0460, wR2 = 0.1154 R1 = 0.0486, wR2 = 0.1061 Final R indexes [all data] R1 = 0.0697, wR2 = 0.1447 R1 = 0.0271, wR2 = 0.0720 R1 = 0.0730, wR2 = 0.1276 R1 = 0.0855, wR2 = 0.1253 Largest diff. peak/hole / e Å-3 0.46/-0.24 0.21/-0.21 0.60/-0.37 0.34/-0.42 Flack Parameter - - - 0.003(6) Table S3: Crystal data and structure refinement details for compounds 6Li, [perylene][K(DME)4], 7Li and 7K. Identification code CCDC Number Empirical formula Formula weight Temperature/K Crystal system Space group a/Å b/Å c/Å α/° β/° γ/° Volume/Å3 Z 8Li 2326098 C74H88Li4Ni2O8 1250.62 100.01(10) triclinic P-1 18.8977(2) 19.4534(2) 22.3454(4) 80.1410(10) 87.6060(10) 89.5510(10) 8086.34(19) 4 8K 2326099 C37H50K2NiO7 743.68 100.15 monoclinic I2/a 26.5914(4) 15.6226(2) 19.9575(3) 90 98.4080(10) 90 8201.8(2) 8 9Li 2326100 C45H61Li2NO5Ni 768.53 173.01(10) monoclinic P21/n 10.61066(4) 10.14415(4) 39.27151(16) 90 94.5490(4) 90 4213.72(3) 4 ρcalcg/cm3 1.027 1.205 1.211 μ/mm-1 F(000) Crystal size/mm3 Radiation 2Θ range for data collection/° 0.51 2656 0.197 × 0.154 × 0.046 Mo Kα (λ = 0.71073) 0.717 3152 0.393 × 0.243 × 0.168 Mo Kα (λ = 0.71073) 1.001 1648 0.236 × 0.174 × 0.076 Cu Kα (λ = 1.54184) 4.208 to 60.068 4.334 to 60.068 4.514 to 148.988 -26 ≤ h ≤ 26, -27 ≤ k ≤ 27, -31 ≤ l ≤ 31 486489 -37 ≤ h ≤ 37, -22 ≤ k ≤ 22, -28 ≤ l ≤ 28 121855 -10 ≤ h ≤ 13, -12 ≤ k ≤ 12, -49 ≤ l ≤ 49 87197 Independent reflections 47321 [Rint = 0.0640, Rsigma = 0.0441] 12004 [Rint = 0.0359, Rsigma = 0.0196] 8616 [Rint = 0.0237, Rsigma = 0.0117] Data/restraints/parameter s 47321/461/1816 12004/80/487 8616/0/491 Goodness-of-fit on F2 1.035 1.036 1.057 Final R indexes [I>=2σ (I)] R1 = 0.0534, wR2 = 0.1316 R1 = 0.0370, wR2 = 0.0933 R1 = 0.0388, wR2 = 0.1080 Final R indexes [all data] R1 = 0.0848, wR2 = 0.1440 R1 = 0.0460, wR2 = 0.0970 R1 = 0.0402, wR2 = 0.1092 Largest diff. peak/hole / e Å-3 0.84/-0.53 0.71/-0.34 0.49/-0.38 Index ranges Reflections collected Table S4: Crystal data and structure refinement details for compounds 8Li, 8K and 9Li. Identification code CCDC Number Empirical formula Formula weight Temperature/K Crystal system Space group a/Å b/Å c/Å α/° β/° γ/° Volume/Å3 Z 10Li 2326101 C76H90Li4N2Ni2O6 1272.67 100.00(10) monoclinic P21/n 13.77390(10) 19.3181(2) 14.30610(10) 90 93.2280(10) 90 3800.61(6) 2 11Li 2326102 C74H88Li4Ni2O8 1250.62 100.01(10) triclinic P-1 18.8977(2) 19.4534(2) 22.3454(4) 80.1410(10) 87.6060(10) 89.5510(10) 8086.34(19) 4 ρcalcg/cm3 1.112 1.027 μ/mm-1 F(000) Crystal size/mm3 Radiation 0.543 1352 0.261 × 0.159 × 0.108 Mo Kα (λ = 0.71073) 0.51 2656 0.197 × 0.154 × 0.046 Mo Kα (λ = 0.71073) 2Θ range for data collection/° 4.216 to 60.444 4.208 to 60.068 -19 ≤ h ≤ 19, -27 ≤ k ≤ 27, -20 ≤ l ≤ 20 225483 -26 ≤ h ≤ 26, -27 ≤ k ≤ 27, -31 ≤ l ≤ 31 486489 Independent reflections 11310 [Rint = 0.0408, Rsigma = 0.0151] 47321 [Rint = 0.0640, Rsigma = 0.0441] Data/restraints/parameters 11310/76/444 47321/461/1816 Goodness-of-fit on F2 1.049 1.035 Final R indexes [I>=2σ (I)] R1 = 0.0394, wR2 = 0.1053 R1 = 0.0534, wR2 = 0.1316 Final R indexes [all data] R1 = 0.0447, wR2 = 0.1079 R1 = 0.0848, wR2 = 0.1440 Largest diff. peak/hole / e Å-3 0.92/-0.31 0.84/-0.53 Index ranges Reflections collected Table S5: Crystal data and structure refinement details for compounds 10Li and 11Li. Solid-State Structure of [(ttt-CDT)NiPh][Li(12-crown-4)2] (1) Figure S9: Solid-state structure of [(ttt-CDT)NiPh][Li(12-crown-4)2] (1). Thermal ellipsoids shown at 30% probability. Hydrogen atoms and disordered components removed and coordinated 12-crown-4 shown as wireframes for clarity. Selected bond lengths [Å]: Ni1–C1 2.024(1); Ni1–C7 2.077(2); Ni1–C8 2.056(2); Ni1–C11 2.106(2); Ni1–C12 2.087(2); Ni1–C15 2.114(2); Ni1–C16 2.083(2); C7–C8 1.384(3); C11–C12 1.386(3); C15–C16 1.384(3). Solid-State Structure of Li4(TMEDA)2(Et2O)2Ph4Ni2(µ;η2;η2-C6H4) (3) Figure S10: Solid-state structure of Li4(TMEDA)2(Et2O)2Ph4Ni2(µ;η2;η2-C6H4) (3). Thermal ellipsoids shown at 30% probability. Hydrogen atoms and disordered components removed and coordinated TMEDA and Et2O shown as wireframes for clarity. Selected bond lengths [Å]: Ni1–C1 1.975(1); Ni1–C7 1.983(1); Ni2–C33 1.973(1); Ni2–C39 1.971(1); Ni1–C19 1.946(1); Ni1–C20 1.966(1); Ni2–C19 1.952(1); Ni2–C20 1.955(1); Ni1–Ni2 2.8538(6); C19–C20 1.424(2). Solid-State Structure of Li2(THF)4Ph2Ni(η2-anthracene) (4Li) Figure S11: Solid-state structure of Li2(THF)4Ph2Ni(η2-anthracene) (4Li). Thermal ellipsoids shown at 30% probability. Hydrogen atoms and disordered components removed and coordinated THF shown as wireframes for clarity. Selected bond lengths [Å]: Ni1–C1 1.966(2); Ni1–C7 1.945(2); Ni1–C13 1.984(2); Ni1–C26 1.986(2); C13–C16 1.462(2). Solid-State Structure of Na2(TMEDA)2Ph2Ni(η2-anthracene) (4Na) Figure S12: Solid-state structure of Na2(TMEDA)2Ph2Ni(η2-anthracene) (4Na). Thermal ellipsoids shown at 30% probability. Hydrogen atoms and disordered components removed and coordinated TMEDA shown as wireframes for clarity. Selected bond lengths [Å]: Ni1–C1 1.964(2); Ni1–C7 1.949(1); Ni1–C25 2.057(2); Ni1–1.954(2); C25–C26 1.449(2). Solid-State Structure of K2(PMDETA)2Ph2Ni(η2-anthracene) (4K) Figure S13: Solid-state structure of K2(PMDETA)2Ph2Ni(η2-anthracene) (4K). Thermal ellipsoids shown at 30% probability. Hydrogen atoms and disordered components removed and coordinated PMDETA shown as wireframes for clarity. Selected bond lengths [Å]: Ni1–C10 1.946(3); Ni1–C16 2.124(3); Ni1– C30 1.886(4); Ni1–C43 2.054(5); C30–C43 1.397(7). Solid-State Structure of Li2(THF)4Ph2Ni(η2-phenanthrene) (5Li) Figure S14: Solid-state structure of Li2(THF)4Ph2Ni(η2-phenanthrene) (5Li). Thermal ellipsoids shown at 30% probability. Hydrogen atoms and disordered components removed and coordinated THF shown as wireframes for clarity. Selected bond lengths [Å]: Ni1–C1 1.955(1); Ni1–C7 1.952(2); Ni1–C13 1.983(2); Ni1–C14 1.976(1); C13–C14 1.453(2). Solid-State Structure of [Na2(THF)3Ph2Ni(η2-phenanthrene)]2 (5Na) Figure S15: Solid-state structure of [Na2(THF)3Ph2Ni(η2-phenanthrene)]2 (5Na). Thermal ellipsoids shown at 30% probability. Hydrogen atoms and disordered components removed and coordinated THF shown as wireframes for clarity. Only one molecule of the asymmetric unit is displayed. Selected bond lengths [Å]: Ni1–C1 1.950(2); Ni1–C7 1.948(2); Ni1–C13 1.976(2); Ni1–C14 1.987(2); C13–C14 1.452(3). Solid-State Structure of [K2(THF)1Ph2Ni(η2-phenanthrene)]∞ (5K) Figure S16: Solid-state structure of [K2(THF)1Ph2Ni(η2-phenanthrene)]∞ (5Na). Thermal ellipsoids shown at 30% probability. Hydrogen atoms and disordered components removed and coordinated THF shown as wireframes for clarity. Selected bond lengths [Å]: Ni1–C15 1.976(3); Ni1–C21 1.946(3); Ni1–C1 2.013(3); Ni1–C2 1.971(3); C1–C2 1.447(4). Solid-State Structure of [Li(THF)2Ph2Ni(η3-perylene)][Li(THF)4] (6Li) Figure S17: Solid-state structure of [Li(THF)2Ph2Ni(η3-perylene)][Li(THF)4] (6Li). Thermal ellipsoids shown at 30% probability. Hydrogen atoms and disordered components removed and coordinated THF shown as wireframes for clarity. Selected bond lengths [Å]: Ni1–C1 1.944(2); Ni1–C7 1.954(2); Ni1–C13 2.171(2); Ni1–C14 1.977(2); Ni1–C15 2.088(2); C13–C14 1.401(3); C14–C15 1.413(3). Solid-State Structure of [perylene][K(DME)4] Figure S18: Solid-state structure of [perylene][K(DME)4]. Thermal ellipsoids shown at 30% probability. Hydrogen atoms removed and coordinated DME shown as wireframes for clarity. During the preparation of this manuscript, an identical crystal structure of [perylene][K(DME)4] was also reported by Balashova and co-workers.12 Solid-State Structure of [Li(THF)2Ph2Ni(η2-coronene)][Li(THF)4] (7Li) Figure S19: Solid-state structure of [Li(THF)2Ph2Ni(η2-coronene)][Li(THF)4] (7Li). Thermal ellipsoids shown at 30% probability. Hydrogen atoms and disordered components removed and coordinated THF shown as wireframes for clarity. Selected bond lengths [Å]: Ni1–C1 1.960(2); Ni1–C7 1.957(2); Ni1–C13 1.983(2); Ni1–C14 2.005(2); C13–C14 1.460(2). Solid-State Structure of K2(DME)4Ph2Ni(η2-coronene) (7K) Figure S20: Solid-state structure of K2(DME)4Ph2Ni(η2-coronene) (7K). Thermal ellipsoids shown at 30% probability. Hydrogen atoms and disordered components removed and coordinated DME shown as wireframes for clarity. Only one molecule in the asymmetric unit is displayed. Selected bond lengths [Å]: Ni1–C41 1.937(6); Ni1–C47 1.936(6); Ni1–C1 1.986(6); Ni1–C2 1.989(7); C1–C2 1.48(1). Solid-State Structure of [Li2(THF)3Ph2Ni(η2-Ph2CO)]2 (8Li) Figure S21: Solid-state structure of [Li2(THF)3Ph2Ni(η2-Ph2CO)]2 (8Li). Thermal ellipsoids shown at 30% probability. Hydrogen atoms and disordered components removed and coordinated THF and phenylsubstituents of Ph2CO shown as wireframes for clarity. Only one molecule in the asymmetric unit is displayed. Selected bond lengths [Å]: Ni3–C71 1.897(2); Ni3–C77 1.970(2); Ni3–C91 1.919(2); Ni3–O11 1.928(1); C91–O11 1.391(2); Ni4–C125 1.956(2); Ni4–C131 1.892(2); Ni4–C112 1.916(2); Ni4–O13 1.924(1); C112–O13 1.389(2). Solid-State Structure of [K2(DME)3Ph2Ni(η2-Ph2CO)]2 (8K) Figure S22: Solid-state structure of [K2(DME)3Ph2Ni(η2-Ph2CO)]2 (8K). Thermal ellipsoids shown at 30% probability. Hydrogen atoms and disordered components removed and coordinated DME and phenylsubstituents of Ph2CO shown as wireframes for clarity. Selected bond lengths [Å]: Ni1–C1 1.929(1); Ni1– C7 1.880(1); Ni1–C13 1.929(2); Ni1–O1 1.928(1); C13–O1 1.375(2). Solid-State Structure of Li2(THF)5Ph2Ni(η2-PhCH=NPh) (9Li) Figure S23: Solid-state structure of Li2(THF)5Ph2Ni(η2-PhCH=NPh) (9Li). Thermal ellipsoids shown at 30% probability. Hydrogen atoms removed and coordinated THF shown as wireframes for clarity. Selected bond lengths [Å]: Ni1–C14 1.929(1); Ni1–C20 1.966(1); Ni1–C1 1.925(1); Ni1–N1 1.956(1); C1–N1 1.419(2). Solid-State Structure of [Li2(THF)3Ph2Ni(η2-Ph2CHCN)]2 (10Li) Figure S24: Solid-state structure of [Li2(THF)3Ph2Ni(η2-Ph2CHCN)]2 (10Li). Thermal ellipsoids shown at 30% probability. Hydrogen atoms and disordered components removed and coordinated THF and phenyl-substituents of Ph2CHCN shown as wireframes for clarity. Selected bond lengths [Å]: Ni1–C1 1.986(1); Ni1–C7 1.932(1); Ni1–C13 1.839(1); Ni1N1 1.954(2); C13–N1 1.242(2). Solid-State Structure of Li(THF)3(PPh3)2(CO)3Ni2(µ-PPh2) (11Li) Figure S25: Solid-state structure of Li(THF)3(PPh3)2(CO)3Ni2(µ-PPh2) (11Li). Thermal ellipsoids shown at 30% probability. Hydrogen atoms and disordered components removed and coordinated THF and phenyl-substituents shown as wireframes for clarity. Selected bond lengths [Å]: Ni1–P1 2.1928(6); Ni1– C1 1.757(2); C1–O1 1.150(3); Ni1–P2 2.2245(4); Ni1–C2 1.902(2); C2–O2 1.187(2); Ni1–Ni2 2.4845(4); Ni2–P2 2.2257(5); Ni2–C2 1.902(2); Ni2–C3 1.746(2); C3–O3 1.154(3); Ni2–P3 2.1967(6). NMR Spectra of Reported Compounds Spectra S1: 1H NMR spectrum of PhLi(Et2O)0.02 in THF-d8. Spectra S2: 7Li NMR spectrum of PhLi(Et2O)0.02 in THF-d8. Spectra S3: 1H NMR spectrum of [(ttt-CDT)NiPh][Li(12-crown-4)2] (1) in THF-d8 at -20 °C. Spectra S4: 7Li NMR spectrum of [(ttt-CDT)NiPh][Li(12-crown-4)2] (1) in THF-d8 at -20 °C. Spectra S5: 13C{1H} NMR spectrum of [(ttt-CDT)NiPh][Li(12-crown-4)2] (1) in THF-d8 at -20 °C. Spectra S6: 1H NMR spectrum of Li2(TMEDA)2Ph2Ni(η2-CDT) (2) in THF-d8. Spectra S7: 7Li NMR spectrum of Li2(TMEDA)2Ph2Ni(η2-CDT) (2) in THF-d8. Spectra S8: 13C{1H} NMR spectrum of Li2(TMEDA)2Ph2Ni(η2-CDT) (2) in THF-d8. Spectra S9: 1H NMR spectrum of Li4(TMEDA)2(Et2O)2Ph4Ni2(µ;η2;η2-C6H4) (3) in THF-d8. Spectra S10: 7Li NMR spectrum of Li4(TMEDA)2(Et2O)2Ph4Ni2(µ;η2;η2-C6H4) (3) in THF-d8. Spectra S11: 13C{1H} NMR spectrum of Li4(TMEDA)2(Et2O)2Ph4Ni2(µ;η2;η2-C6H4) (3) in THF-d8. Spectra S12: 1H NMR spectrum of Li2(THF)4Ph2Ni(η2-anthracene) (4Li) in THF-d8. * Unidentified impurity. Spectra S13: 7Li NMR spectrum of Li2(THF)4Ph2Ni(η2-anthracene) (4Li) in THF-d8. Spectra S14: 13C{1H} NMR spectrum of Li2(THF)4Ph2Ni(η2-anthracene) (4Li) in THF-d8. Spectra S15: 1H NMR spectrum of Na2(TMEDA)2Ph2Ni(η2-anthracene) (4Na) in THF-d8. * Unidentified impurity. Spectra S16: 13C{1H} NMR spectrum of Na2(TMEDA)2Ph2Ni(η2-anthracene) (4Na) in THF-d8. * C6H6. Spectra S17: 1H NMR spectrum of K2(PMDETA)2Ph2Ni(η2-anthracene) (4K) in THF-d8. Spectra S18: 13C{1H} NMR spectrum of K2(PMDETA)2Ph2Ni(η2-anthracene) (4K) in THF-d8. Spectra S19: 1H NMR spectrum of Li2(THF)4Ph2Ni(η2-phenanthrene) (5Li) in THF-d8. Spectra S20: 7Li NMR spectrum of Li2(THF)4Ph2Ni(η2-phenanthrene) (5Li) in THF-d8. Spectra S21: 13C{1H} NMR spectrum of Li2(THF)4Ph2Ni(η2-phenanthrene) (5Li) in THF-d8. Spectra S22: 1H NMR spectrum of [Na2(THF)3Ph2Ni(η2-phenanthrene)]2 (5Na) in THF-d8. * Residual Et2O. Spectra S23: 13C{1H} NMR spectrum of [Na2(THF)3Ph2Ni(η2-phenanthrene)]2 (5Na) in THF-d8. Spectra S24: 1H NMR spectrum of [K2(THF)1Ph2Ni(η2-phenanthrene)]∞ (5K) in THF-d8. * Residual Et2O and pentane. Spectra S25: 13C{1H} NMR spectrum of [K2(THF)1Ph2Ni(η2-phenanthrene)]∞ (5K) in THF-d8. Spectra S26: 1H NMR spectrum of [Li(THF)2Ph2Ni(η3-perylene)][Li(THF)4] (6Li) in THF-d8. Spectra S27: 7Li NMR spectrum of [Li(THF)2Ph2Ni(η3-perylene)][Li(THF)4] (6Li) in THF-d8. Spectra S28: 13C{1H} NMR spectrum of [Li(THF)2Ph2Ni(η3-perylene)][Li(THF)4] (6Li) in THF-d8. Spectra S29: 1H NMR spectrum of [Li(THF)2Ph2Ni(η2-coronene)][Li(THF)4] (7Li) in THF-d8 at -20 °C. Spectra S30: 7Li NMR spectrum of [Li(THF)2Ph2Ni(η2-coronene)][Li(THF)4] (7Li) in THF-d8 at -40 °C. Spectra S31: 13C{1H} NMR spectrum of [Li(THF)2Ph2Ni(η2-coronene)][Li(THF)4] (7Li) in THF-d8 at -20 °C. Spectra S32: 1H NMR spectrum of K2(DME)4Ph2Ni(η2-coronene) (7K) in THF-d8. Spectra S33: Stacked 1H NMR spectra of [Li2(THF)3Ph2Ni(η2-Ph2CO)]2 (8Li) in THF-d8 at -20 °C (blue trace) and +20 °C (red trace). * Residual Et2O. Spectra S34: Stacked 7Li NMR spectra of [Li2(THF)3Ph2Ni(η2-Ph2CO)]2 (8Li) in THF-d8 at -20 °C (blue trace) and +20 °C (red trace). * Unidentified impurities. Spectra S35: 13C{1H} NMR spectra of [Li2(THF)3Ph2Ni(η2-Ph2CO)]2 (8Li) in THF-d8 at -20 °C. Spectra S36: 1H NMR spectrum of [K2(DME)3Ph2Ni(η2-Ph2CO)]2 (8K) in THF-d8. Spectra S37: 13C{1H} NMR spectrum of [K2(DME)3Ph2Ni(η2-Ph2CO)]2 (8K) in THF-d8. Spectra S38: 1H NMR spectrum of Li2(THF)5Ph2Ni(η2-PhCH=NPh) (9Li) in THF-d8. Spectra S39: 7Li NMR spectrum of Li2(THF)5Ph2Ni(η2-PhCH=NPh) (9Li) in THF-d8. Spectra S40: 13C{1H} NMR spectrum of Li2(THF)5Ph2Ni(η2-PhCH=NPh) (9Li) in THF-d8. Spectra S41: 1H NMR spectrum of [Li2(THF)3Ph2Ni(η2-Ph2CHCN)]2 (10Li) in THF-d8 at -20 °C. * Unidentified impurities/decomposition products. Spectra S42: 7Li NMR spectrum of [Li2(THF)3Ph2Ni(η2-Ph2CHCN)]2 (10Li) in THF-d8 at -20 °C. Spectra S43: 1H NMR spectrum of Li(THF)3(PPh3)2(CO)3Ni2(µ-PPh2) (11Li) in THF-d8. Spectra S44: 7Li NMR spectrum of Li(THF)3(PPh3)2(CO)3Ni2(µ-PPh2) (11Li) in THF-d8. Spectra S45: 31P NMR spectrum of Li(THF)3(PPh3)2(CO)3Ni2(µ-PPh2) (11Li) in THF-d8. Spectra S46: 13C{1H} NMR spectrum of Li(THF)3(PPh3)2(CO)3Ni2(µ-PPh2) (11Li) in THF-d8. Reference Spectra Spectra S47: 1H NMR spectrum of phenanthrene in THF-d8. 1H NMR (300.1 MHz, THF-d8): δ 8.75 (dd, J = 7.9, 1.2 Hz, 2H), 7.89 (m, 2H), 7.74 (s, 2H), 7.66–7.53 (m, 4H). Spectra S48: 13C{1H} NMR spectrum of phenanthrene in THF-d8. 13C{1H} NMR (75.5 MHz, THF-d8): δ 133.3, 131.5, 129.5, 127.8, 127.5, 127.5, 123.7. Spectra S49: 1H NMR spectrum of N-benzylideneaniline in THF-d8. 1H NMR (300.1 MHz, THF-d8): δ 8.50 (s, 1H), 7.96–7.88 (m, 2H), 7.48–7.41 (m, 3H), 7.38–7.31 (m, 2H), 7.24–7.14 (m, 3H). Spectra S50: 13C{1H} NMR spectrum of N-benzylideneaniline in THF-d8. 13C{1H} NMR (75.5 MHz, THFd8): δ 160.8, 153.4, 137.9, 132.1, 129.9, 129.7, 129.6, 126.7, 121.8. Spectra S51: 1H NMR spectrum of diphenylacetonitrile in THF-d8. 1H NMR (300.1 MHz, THF-d8): δ 7.41–7.24 (m, 10H), 5.42 (s, 1H). Spectra S52: 13C{1H} NMR spectrum of diphenylacetonitrile in THF-d8. 13C{1H} NMR (75.5 MHz, THFd8): δ 138.2, 130.0, 128.9, 128.7, 120.4, 42.9. In Situ Synthesis and Characterisation of Imine Addition Product, Ph2CHN(Li)Ph N-benzylideneaniline (18.1 mg, 0.1 mmol) was dissolved in THF-d8 (0.5 mL) and cooled to -30 °C. PhLi (8.6 mg, 0.1 mmol) was added and the colourless solution was warmed to room temperature. 1H NMR spectroscopy indicated clean nucleophilic addition of PhLi across the C=N bond to give Ph2CHN(Li)Ph. Spectra S53: 1H NMR spectrum of Ph2CHN(Li)Ph prepared in situ in THF-d8. 1H NMR (300.1 MHz, THFd8): δ 7.28 (m, 4H, Ph2-o-CH), 7.15 (t, J = 7.6 Hz, 4H, Ph2-m-CH), 7.03 (tt, J = 7.2, 1.4 Hz, 2H, Ph2-pCH), 6.61 (dd, J = 7.1, 1.6 Hz, 2H, N-Ph-m-CH), 6.00 (br d, J = 7.0 Hz, 2H, N-Ph-o-CH), 5.74 (tt, J = 7.0, 1.0 Hz, 1H, N-Ph-p-CH), 5.25 (s, 1H, CH). Spectra S54: 7Li NMR spectrum of Ph2CHN(Li)Ph prepared in situ in THF-d8. 7Li NMR (116.6 MHz, THF-d8): δ 0.63 (s). Spectra S55: 13C{1H} NMR spectrum of Ph2CHN(Li)Ph prepared in situ in THF-d8. 13C{1H} NMR (75.5 MHz, THF-d8): δ 161.8 (N-Ph-ipso-C), 150.7 (Ph2-ipso-C), 129.2 (Ph2-o-CH), 129.0 (br, N-Ph-m-CH), 128.6 (Ph2-m-CH), 126.0 (Ph2-p-CH), 113.9 (br, N-Ph-o-CH), 106.9 (N-Ph-p-CH), 68.5 (CH). In Situ Synthesis and Characterisation of Lithiated Diphenylketenimine, Ph2C=C=N–Li Diphenylacetonitrile (19.3 mg, 0.1 mmol) was dissolved in THF-d8 (0.5 mL) and cooled to -30 °C. PhLi (8.6 mg, 0.1 mmol) was added leading to a colour change from colourless to pale yellow upon warming to room temperature. H NMR spectroscopy indicated the clean α-deprotonation to give the lithiated 1 diphenylketenimine alongside benzene. Spectra S56: 1H NMR spectrum of lithiated diphenylketenimine prepared in situ in THF-d8. 1H NMR (300.1 MHz, THF-d8): δ 7.23 (dd, J = 7.4, 1.2 Hz, 4H, Ph-o-CH), 6.88 (m, 4H, Ph-m-CH), 6.36 (tt, J = 7.1, 1.2 Hz, 2H, Ph-p-CH). Spectra S57: 7Li NMR spectrum of lithiated diphenylketenimine prepared in situ in THF-d8. 7Li NMR (116.6 MHz, THF-d8): δ -0.27 (s). Spectra S58: 13C{1H} NMR spectrum of lithiated diphenylketenimine prepared in situ in THF-d8. 13C{1H} NMR (75.5 MHz, THF-d8): δ 145.4 (Ph-ipso-C), 140.0 (C=C=N), 128.4 (Ph-m-CH), 122.2 (Ph-o-CH), 116.6 (Ph-p-CH), 54.6 (C=C=N). References (1) Borys, A. M. The Schlenk Line Survival Guide https://schlenklinesurvivalguide.com. (Accessed March 2024) (2) Borys, A. M. An Illustrated Guide to Schlenk Line Techniques. Organometallics 2023, 42 (3), 182– 196. https://doi.org/10.1021/acs.organomet.2c00535. (3) Bogdanović, V. B.; Kröner, M.; Wilke, G. Olefin Complexes of Nickel(0). Liebigs Ann. Chem 1966, 669 (1), 1–23. https://doi.org/10.1002/jlac.19666990102. (4) Borys, A. M.; Hevia, E. The Anionic Pathway in the Nickel‐Catalysed Cross‐Coupling of Aryl Ethers. Angew. Chem. Int. Ed. 2021, 60 (46), 24659–24667. https://doi.org/10.1002/anie.202110785. (5) Neufeld, R.; Stalke, D. Accurate Molecular Weight Determination of Small Molecules via DOSYNMR by Using External Calibration Curves with Normalized Diffusion Coefficients. Chem. Sci. 2015, 6 (6), 3354–3364. https://doi.org/10.1039/c5sc00670h. (6) Bachmann, S.; Gernert, B.; Stalke, D. Solution Structures of Alkali Metal Cyclopentadienides in THF Estimated by ECC-DOSY NMR-Spectroscopy. Chem. Commun. 2016, 52 (87), 12861–12864. https://doi.org/10.1039/c6cc07273a. (7) Bachmann, S.; Neufeld, R.; Dzemski, M.; Stalke, D. New External Calibration Curves (ECCs) for the Estimation of Molecular Weights in Various Common NMR Solvents. Chem. Eur. J. 2016, 22 (25), 8462–8465. https://doi.org/10.1002/chem.201601145. (8) Oxford-Diffraction. CrysAlisPro. Oxford Diffraction 2018. (9) Sheldrick, G. M. A Short History of SHELX. Acta Cryst. 2008, 64 (1), 112–122. https://doi.org/10.1107/S0108767307043930. (10) Sheldrick, G. M. Crystal Structure Refinement with SHELXL. Acta Cryst. 2015, C71, 3–8. https://doi.org/10.1107/S2053229614024218. (11) Dolomanov, O. V.; Bourhis, L. J.; Gildea, R. J.; Howard, J. A. K.; Puschmann, H. OLEX2: A Complete Structure Solution, Refinement and Analysis Program. J. Appl. Crystallogr. 2009, A42 (2), 339–341. https://doi.org/10.1107/S0021889808042726. (12) Balashova, T. V; Polyakova, S. K.; Ilichev, V. A.; Baranov, E. V; Fukin, G. K.; Kozhanov, K. A.; Zhigulin, G. Y.; Ketkov, S. Y.; Bochkarev, M. N. 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