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Mitochondria-targeted half-sandwich rutheniumII diimine complexes: anticancer and antimetastasis via ROS-mediated signalling
ISSN: 2320-5407
Int. J. Adv. Res. 11(02), 1145-1151
Journal Homepage: - www.journalijar.com
Article DOI: 10.21474/IJAR01/16358
DOI URL: http://dx.doi.org/10.21474/IJAR01/16358
RESEARCH ARTICLE
THEMIZOROKI HECK REACTION IN AQUEOUS SOLVENTS PROMOTED BY RESIN-SUPPORTED
OF NOVEL RPF@PDNPS NANOSPHERES: CATALYTIC REDUCTION TEST
1.
2.
Busroni Busron1, Suyanta2 and Chairil Anwar2
Departement of Chemistry, Faculty of Mathematics and Natural Sciences Jember University, Jl. Kalimantan 37,
Jember 681752.
Departement of Chemistry, Faculty of Mathematics and Natural Sciences Gadjah Mada University, Jl. Sekip
Utara, Yogyakarta 55281.
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Manuscript Info
Abstract
…………………….
………………………………………………………………
Manuscript History
Received: 31 December 2022
Final Accepted: 31 January 2023
Published: February 2023
Key words:RPF (Formaldehyde Phenol Resin),
Aldol
Condensation,
Nanospheres,
Catalytic
Reduction,
Nanoparticle
Palladium
The aim of the research was to synthesize formaldehyde phenolic resin
(RPF) nanospheres using the aldol condensation method. The Novel of
RPF@PdNPs Nanospheres that were prepared at that time was used as
a reducing agent and stabilizing supported for the synthesis of PdNPs
nanoparticles. It turns out phenol replacement led to a significant
decrease in nanosphere size and an increase in the surface roughness of
the nanospheres, which ultimately increases the specific surface area of
the RPF nanospheres. Because of enhanced specific surface area and
excellent reducing activity of RPF (Formaldehyde Phenol Resin),
prepared RPF nanospheres have a very high amount of PdNPs loading.
Therefore, the as-prepared of RPF@PdNPs nanospheres exhibit a
highly efficient catalytic capability for the reduction of Cr(VI) toxicity.
Copy Right, IJAR, 2023,. All rights reserved.
……………………………………………………………………………………………………....
Introduction:Precious metal NPs have been of great interest stemming from their various useful applications in various fields,
such as in sensors, biomedical treatment, energy conversion, catalysis, and so on (Chen et al., 2020). Among all the
precious metal NPs, Palladium NPs have attracted considerable attention, as it has great catalytic activity and a
remarkable hydrogen adsorption capacity at low temperatures around 50 0C (Li et al., 2009). Therefore, Pd NPs are
widely used as effective catalysts for the rapid elimination of organic pollutants and heavy metals by the catalytic
transformation of these pollutants. (Han et al., 2016; Veerakumar et al., 2017). In particular, Pd-based catalytic
reduction shows high potential in the treatment of wastewater containing hexavalent Cr (VI) chromium, as it can
convert the highly toxic Cr(VI) to relatively non-toxic and inert Cr(III) which can be easily removed. from an
aqueous system in the form of insoluble hydroxide (Liu Q. et al., 2016). Nanoparticles are widely used as catalysts,
antibacterial, and antioxidants, as well as anticancer. The nanoparticle structure is composed of metal, non-metal
(organic), or mixed atoms. The nanoparticles are hydrophobic and the surface of the nanoparticles is often coated
with a polymer to stabilize the metal. Chemical synthesis of metal nanoparticles was carried out by forming metal
atoms from the reduction of metal precursors using chemical reducing agents, such as NaBH4, HCOOH, PANI, and
Polypyrrorole. The formed metal atoms will experience nucleation followed by growth which will produce
nanoparticles. Nucleation can occur because supersaturated solutions are thermodynamically unstable. Metal
nanoparticles have a solid three-dimensional structure. These particles are made by reducing metal ions into zerovalent and uncharged metals. The reaction process for the formation of nanoparticles by means of charged metal
ions such as Au, Pt, Ag, Pd, Co, Fe is reduced with reducing agents such as sodium citrate, sodium borohydride,
Corresponding Author:- Busroni Busron
Address:- Departement of Chemistry, Faculty of Mathematics and Natural Sciences
Jember University, Jl. Kalimantan 37, Jember 681752.
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Int. J. Adv. Res. 11(02), 1145-1151
hydrazine, polyaniline, and polypyrrole (Wulandari, 2021). Among the reactions catalyzed by palladium, the
arylation of alkenes called the Mizoroki–Heck reaction is the most important carbon-carbon bond formation process.
Over the last 25 years, a large number of applications have been developed on a laboratory and industrial scale
(Alacid E. and Carmen Nájera, 2008), All Chromium valence (VI) compounds are toxic (because of their
oxidizing power), and carcinogenic, especially if airborne and inhaled where they can cause lung cancer, and nose
and nasal sinus cancer. The use of chromate compounds in manufactured goods is also restricted. Therefore,
remediation is needed to reduce the impact on humans and ecosystems. Chromium valence (III) has an octahedral
coordination configuration, and its complexes are generally inert. In an aqueous environment, which contains
oxygen-based species, chromate complexes (Omole et al., 2017).Nanotechnology has become an important research
area in the development of engineered materials that can be integrated into technology. The synthesis and selective
application of engineered materials are very important for the development of nano-functional devices. Metalpolymer nanocomposite materials are expected to become an important class of materials in nanotechnology. These
engineered materials have very different electronic and optical properties from the original nanoparticles. Artificial
nanocomposites displaying novel properties can be synthesized by careful selection and appropriate combinations of
the two components (Athawale et al., 2006)..The Catalytic activity of the Pd@ZIF-67 The catalytic activity of the
Pd@ZIF-67 was evaluated in the aqueous reduction of Cr(VI) to Cr(III) with formic acid (HCOOH). In a typical
process, a mixture containing 5.89 mg (2.0 mM) of K2Cr2O7, 173.2 μL (0.45 M) of HCOOH, 312.3 mg (0.45 M) of
HCOONa, and 10 mL of Milli-Q water was added into a round-bottom flask, and magnetically stirred at ambient
temperature for 15 min, then 2 mg of the Pd@ZIF-67 catalyst was introduced into the flask, and the reduction
reaction started (t=0 min) with magnetic stirring. At given time intervals, 100 μL of the reaction solution was
withdrawn and diluted to 1.0 mL to monitor the transformation of Cr(VI) to Cr(III) using a UV–vis spectrometer
(UV-2450, SHIMADZU)(Li H.C. et al., 2016).Busroni et al., 2022, reported that the C-4phenylcalix[4]resorcinarene-nanopalladium compound can be synthesized via several reaction routes in succession:
One of the reaction steps for the synthesis of palladium nanoparticles is the reduction process of palladium[II] to
palladium[0] in the presence of phenylhydrazine. Several researchers related to the formation of etherification
reactions and continued the complexation route between palladium[II] cations and calix[4]resorcinarene derivatives.
Most of the transition metal nanoparticles such as palladium, nickel, gold, silver, and platinum have been studied
and used for different catalytic applications. The catalytic activity of metal nanoparticles depends on their smaller
size with a large surface area ratio and produces very good yields and very efficient reaction times. Palladium
nanoparticles are very sensitive to many carbon-carbon coupling reactions such as the Mizoroki-Heck reaction
(Kongor, A., etal., 2016).Athawale (2003) and Marulasiddeshwara, (2015), reported that the synthesis of
Palladium nanoparticles (Pd@NPs) can be synthesized by two different methods namely. reflux and irradiation as
well as research related to the stability of the synthesized nanoparticles. Among the various stabilizers added.
polyaniline was found to be the most effective. Pd metal was chosen because Pd is an interesting transition metal
element from the point of view of magnetism and has very good catalytic activity. In order to permanently maintain
the zerovalent state of metals, solution polymerization of empty nanoparticles containing polyaniline and
polypyrrole has been carried out to obtain “MetalPolymer” or “OrganoMetal” nanocomposites. Zero valent
palladium can catalyze the Mizoroki–Heck, and Suzuki-Miyaura reactions and is the strongest and best synthetic
material for forming carbon-carbon bonds in organic syntheses, such as in arylation, alkylation, or vinylation
reactions with alkenes through reactions with aryl, vinyl, benzyl or allyl halides in the presence of a base, andthe
carbon-carbon joining reaction catalyzed by transition metal nanoparticles of aryl or alkenyl halides with
olefins/alkenes is known as the Mizoroki-Heck reaction. This reaction is one of the best methods for the rapid
formation of carbon-carbon bonds (Lin B.L. et al., 2003).
Experimental
Material:Synthesis Material of Novel RPF@PdNPs; according to(Shillin Chen et all., 2020), K2Cr2O7, Ethanol,
Aquadest, PdCl2 (Merck), HCOOH (Merck)
Instrumentation
The instruments used in this study consist of laboratory glassware, heating, and magnetic stirring analytical scales;
Buchii evaporators (R-124),spectrophotometry infrared (FTIR, Genesys) UV-Vis.
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Procedure:Synthesis ofPhenol Formaldehyde Resin (RPF) nanospheres
Synthesized formaldehyde phenolic resin (RPF) nanospheres using the aldol condensation methodwere prepared
following a modified method (Shilin et. al., 2020). Specifically, 0.12 g of phenol, 0.28 g of 37% formaldehyde
solution, and 0.04 g of NaOH are weighed and then mixed sufficiently in 28 mL of aqueous ethanol solution (8 mL
of ethanol and 20 mL of distilled water). The prepared solutions were then heated at 75°C for 2 hours and 90°C for
30 minutes, respectively. Thereafter, the solution was transferred into and heated at 120 °C for 1 hour, followed by
natural cooling to room temperature. The solid product was collected by centrifugation and washed several times
with distilled water and ethanol respectively. Finally, the thermo-setting RPF nanospheres were obtained by drying
in a vacuum oven at 30 °C for 24 h.
Synthesis of RPF@PdNPsnanospheres by (Shilin Chen, 2020)
Typically, 60 mg asprepared PRF nanospheres were dispersed into 20 mL deionized water, then 20 mg PdCl2 was
added and the mixture was stirred using a magnetic stirrer at 80°C for 7 hours. After continuous stirring, the initial
pale yellow solution progressively white-darkened, suggesting the formation of the PdNPs. The products were
collected by centrifugation or filtered and washed with ethanol and deionized water three times, respectively, and
followed by drying at 50 °C overnight to obtain RPF@PdNPs nanospheres. For comparison purposes, RPF@PdNPs
nanospheres were also prepared using the same procedure as followed for RPF@PdNPs.The residue was air dried
for 24 hours to produce an initial pale yellow to white darkened powder of RPF@PdNPs nanocomposite containing
zero-valence palladium. The results of the RPF@PdNPs nanospheres as a catalyst were characterized using Figure
1. FTIR spectra, and Figure 2. UV-Vis spectra. Figure 3. Structure of RPF@PdNPs nanospheres, solid whitedarkened.
Catalytic Reduction Test
Potassium dichromate (K2Cr2O7) was chosen as one of the representative Cr(VI) compounds for catalytic reduction
experiments. It is known that the characteristic absorption peak of Cr(VI) centered at 350 nm (Shilin C. et al., 2020)
is caused by a ligand-to-metal charge transfer transition. Thus, in the RPF@PdNPs nanospheres for the catalytic
reduction process, it was observed that after the addition of the RPF@PdNPs. Decreased in color from orange to
white at 30 minutes, accompanied by a color change from yellow to colorless, this indicates that there has been a
reduction of Cr(VI). The reduction reaction is considered complete when the main absorption peak at 350 nm
disappears or the absorption peak of Cr(VI) ions becomes Cr(III) or Cr(VI) becomes zero-valence Cr(0)(Shilin
Chen, 2020)
Result and Discussion:Investigation with FTIR Novel of RPF@PdNPsnanospheres
Figure 1:- Spectra FTIR of Novel RPF@PdNPs nanospheres.
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However, a comparison of the FT-IR spectra of samples exposed to nanospheres and exposed Palladium(II) ions
indicated that there were two significant differences in the absorption area of 3000 - 3500 cm-1 where there was
interaction with Pd(II) resulting in the reduction of Pd(II) ions. to Pd(0), this can be indicated from the results of the
investigation that there was a change in the color of the Phenol Formaldehyde Resin (RPF) in which the yellow or
pale yellow solid turned into a white-black or white-darkened color. A literature study by Busroni et al., 2022 and
Shilin et al., 2020, that black is a Palladium color with zero valences. While the white-dark color is zero valent
palladium which interacts with OH ligands or OH groups in the nanospheres form of RPF@PdNPs or palladium
nanoparticles in the presence of hydroxy groups in Phenol Formaldehyde Resin during the interaction. The reaction
interaction model is shown in Figure 2 UV-Vis analysis is bellow.
Investigation with UV-Vis Novel of RPF@PdNPsnanospheres
Investigation using UV-vis spectroscopy to track the occurrence of changes in Pd(II) to Pd(0), based on the results
of this study that the RPF@PdNPs nanosphereswere used by the research group to synthesize palladium
nanoparticles. To this knowledge, no one has reported the use of RPF@PdNPs nanospheres as reducing and
stabilizing agents to synthesize nanoparticles, in particular, PdNPs or palladium nanoparticles. Herein have been
prepared PdNPs using palladium chloride and RPF in water without the use of external reducing agents or
stabilizers. Thus, dispersible in water, RPF@PdNPs nanospheres are formed by chemical reduction in one method.
The morphology of the formed nanoparticles was investigated by UV-Vis spectroscopy. The addition of palladium
chloride to the hot RPF (Formaldehyde Phenol Resin) solution appeared at 80 0C and showed a color change from
pale yellow to white-dark after stirring for 8 hours. After 8 hours previously confirmed the formation of colloidal
RPF@PdNPs nanospheres as catalysts. The UV–vis spectrum was taken to monitor and investigate the maximum
absorption of the analysis results using the UV-Vis material RPF@PdNPs formed. The maximum absorption was
obtained at a wavelength at 291 nm in Figure 3. Palladium chloride solution gives a broad maximum absorption
band of 400-600 nm which refers to the presence of Pd(II).Lostof band at 450 nm (PdCl2.5H2O)(Busroni et al.,
2022). it was found that due to the reduction of Pd(II) to Pd(0) the oxidation state confirmed as a comparison of the
formation of PdNPs there was an absorption change of around 250 nm as Pd(0) based on the results of the research
of Panchal et al., 2018, PdCl2. 5H2O the aqueous solution was added to the same volume of hot water solution PdCl2.
5H2O. Theresulting mixture was kept under vigorous stirring and heated at 800C for 6 hours. The reduction of
palladium was confirmed by a color change from pale-yellow to white-darkened, meaning that there was a change in
absorption of Pd(II) to Pd(0). There was a change in absorption from 450 to 291 nm, confirmed using UV-Vis
spectroscopy as water-insolubleRPF@PdNPs nanospheres and reduced Pd(0) zero valence in RPF@PdNPs.Thus the
results of RPF@PdNPs are then used to carry out the catalytic test process. UV-Visible spectroscopy was mainly
used to evaluate the formation of RPF@PdNPs and the different color changes from pale-yellow to white-darkened,
confirming the formation of RPF@PdNPs in Figure 2, according to the results of research by (Kongor et al., 2016
and Panchal, et al., 2018)
Figure 2:- UV-Vis Analysis of RPF@PdNPs nanospheres.
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Figure 3:- Spectra UV-Vis analysis of KAROPH-PdNPs (Busroni et al., 2022).
Based on the UV-Visible investigation of the Pd(II), the results of the investigation using UV-Vis obtained the
maximum absorption Pd(0) at 450 nm in the KAROPH-PdNPs(Busroni et al., 2022), the results of the analysis using
UV-Vis obtained absorption at 200-250 nm (Boeva et al., 2014) meaning that there had been a reduction process by
the hydrazine group and absorption at 450 nm had disappeared [Busroni et al., 2022), while the composite of
RPF@PdNPsnanospheres, Figure 3 the results of the analysis used UV-Vis obtained the maximum absorption at 291
nm, meaning that there had been lost. The addition of Pd(II) ion solution to the RPF@PdNPssolution in situ and
heated to 500C showed a color change from pale-yellow to white-darkened. After six hours the previously confirmed
formation of the RPF@PdNPs colloid or suspension. The UV–vis spectrum was taken to monitor and verify the
formed RPF@PdNPs nanospheres as a catalyst. Palladium chloride solution gives a broad maximum absorption
band around 400-600 nm which refers to the presence of Pd(II). The loss of the band at 450 nm in Figure 3
according to the results of UV-Vis investigation in Figure 3(Busroni et al., 2022), was found due to the reduction of
Pd(II) to Pd(0) the oxidation state confirmed the formation of PdNPs changes absorption around 291 nm as Pd(0) in
Figure 3. Then the presence was compared based on the results (Torshizi et al., 2016), and an aqueous solution of
PdCl2.5H2O was added to the same volume of hot water solution of PdCl2.5H2O. The resulting mixture was kept
under vigorous stirring and heated at 800C for 6 hours.
CatalyticReduction Test
Potassium dichromate (K2Cr2O7) was chosen as one of the representative Cr(VI) compounds for catalytic reduction
experiments. It is known that the characteristic absorption peak of Cr(VI) centered at 350 nm (Shilin C., et al., 2020)
is caused by a ligand-to-metal charge transfer transition. Thus, in the RPF@PdNPs nanospheres as a catalytic
reduction process, it was observed that after the addition of the RPF@PdNPs as the catalyst, the absorption peak
intensity at 350 nm changed (Figure 2. UV-Vis decreased in color from orange to yellow-green with increasing
reaction time accompanied by a color change from yellow to colorless, this indicates that there has been a reduction
of Cr(VI). The reduction reaction is considered complete when the main absorption peak at 350 nm disappears or the
absorption peak of Cr(VI) ions decreases to Cr( III) or Cr(VI) to zero valences Cr(0) according to the research
results of Shilin Chen, 2020. The interaction model for the catalytic reduction reaction is shown in Figure 4 below
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Figure 4:- Catalytic Reduction Test of Novel RPF@PdNPs onto K2Cr2O7Using HCOOH.
Conclusion:A methodology has been developed for the synthesis of RPF@PdNPs nanospheres, and subsequent reduction of
PdNPs without the addition of reducing agents or stabilizers. The catalytically active PdNPs nanoparticles dispersed
well on the surface of the RPF nanospheres. Incorporation of Formaldehyde in Phenol Resin results in the surface of
RPF nanospheres. The incorporation of Formaldehyde in Phenol Resin results in an increase in surface roughness,
which increases the specific surface area of the RPF nanospheres. In addition, the formed RPF nanospheres inherited
the reducing activity of the hydroxy ligands, which further increased the number of PdNPs nanoparticles. Thus, the
novel catalyst RPF@PdNPs exhibits highly efficient catalytic activity in the reduction process of the toxic and
hazardous Cr(VI). In addition, RPF@PdNPs nanospheres and excellent reusability in reducing Cr(VI). Therefore,
the high catalytic and reusable of RPF@PdNPs nanospheres, together with the relatively easy reduction preparation,
demonstrates the excellent potential of this functionalized material in catalytic and wastewater treatment
applications
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