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Öğe Amine-functionalized graphene nanosheet-supported PdAuNi alloy nanoparticles: efficient nanocatalyst for formic acid dehydrogenation(Royal Soc Chemistry, 2018) Bulut, Ahmet; Yurderi, Mehmet; Kaya, Murat; Aydemir, Murat; Baysal, Akin; Durap, Feyyaz; Zahmakiran, MehmetFormic acid (HCOOH), a major by-product of biomass processing with high energy density, stability and non-toxicity, has a great potential as a safe and a convenient liquid hydrogen (H-2) storage material for combustion engines and fuel cell applications. However, high-purity hydrogen release from the catalytic decomposition of aqueous formic acid solution at desirable rates under mild conditions stands as a major challenge that needs to be solved for the practical use of formic acid in on-demand hydrogen generation systems. Described herein is a new nanocatalyst system comprised of 3-aminopropyltriethoxysilane-functionalized graphene nanosheet-supported PdAuNi alloy nanoparticles (PdAuNi/f-GNS), which can reproducibly be prepared by following double solvent method combined with liquid-phase chemical reduction, all at room temperature. PdAuNi/f-GNS selectively catalyzes the decomposition of aqueous formic acid through the dehydrogenation pathway (similar to 100% H-2 selectivity), in the absence of any promoting additives (alkali formates, Bronsted bases, Lewis bases, etc.). PdAuNi/f-GNS nanocatalyst provides CO-free H-2 generation with a turnover frequency of 1090 mol H-2 mol metal(-1) h(-1) in the additive-free dehydrogenation of formic acid at almost complete conversion (>= 92%) even at room temperature. The catalytic activity provided by PdAuNi/f-GNS nanocatalyst is higher than those obtained with the heterogeneous catalysts reported to date for the additive-free dehydrogenation of formic acid. Moreover, PdAuNi/f-GNS nanoparticles show high durability against sintering, clumping and leaching throughout the catalytic runs, so that the PdAuNi/f-GNS nanocatalyst retains almost its inherent catalytic activity and selectivity at the end of the 10th recycle.Öğe Aminophosphine-palladium(II) complexes: Synthsesis, structure and applications in Suzuki and Heck cross-coupling reactions(Elsevier Science Sa, 2011) Aydemir, Murat; Baysal, Akin; Sahin, Ertan; Gumgum, Bahattin; Ozkar, SaimReaction of furfurylamine with 1 or 2 equivalents of PPh2Cl in the presence of Et3N, proceeds under anaerobic conditions in thf to give furfuryl-2-(N-diphenylphosphino)amine, Ph2PNHCH2-C4H3O, 1 and furfuryl-2-(N,N-bis(diphenylphosphino)amine), (Ph2P)(2)NCH2-C4H3O, 2, respectively. The reactions of 1 and 2 with MCl2(cod) (M = Pd, Pt; cod = 1,5-cyclooctadiene) or Pt(CH3)(2)(cod) yield complexes [M(Ph2PNHCH2-C4H3O)(2)Cl-2] (M= Pd 1a, Pt 1b), [Pt(Ph2PNHCH2-C4H3O)(2)(CH3)(2)] (1c), and [M((Ph2P)(2) NCH2-C4H3O)Cl-2] (M= Pd 2a, Pt 2b), [Pt((Ph2P)(2)NCH2-C4H3O)(CH3)(2)] (2c), respectively. All the compounds were isolated as analytically pure substances and characterized by NMR, IR spectroscopy and elemental analysis. Representative solid-state structures of 2a and 2b were also determined by X-ray single crystal diffraction technique. Furthermore, the palladium complexes 1a and 2a were tested and found to be highly active catalysts in the Suzuki coupling and Heck reaction affording biphenyls and trans-stilbenes, respectively. (C) 2011 Elsevier B.V. All rights reserved.Öğe Applications of transition metal complexes containing 3,3?-bis(diphenylphosphinoamine)-2,2?-bipyridine ligand to transfer hydrogenation of ketones(Elsevier Science Sa, 2012) Aydemir, Murat; Meric, Nermin; Baysal, AkinHydrogen transfer reduction processes are attracting increasing interest from synthetic chemists in view of their operational simplicity. 3,3'-bis(diphenylphosphinoamine)-2,2'-bipyridine, (Ph2PNH)(2)C10H6N2, was prepared through a single step reaction of 3,3'-diamino-2,2'-bipyridine with diphenyl-chlorophosphine. Reaction of (Ph2PNH)(2)C10H6N2 with [Ru(eta(6)-benzene)(mu-Cl)Cl](2), [Rh(mu-Cl)(cod)](2) or [Ir(eta(5)-C5Me5)(mu-Cl)Cl](2) gave a range of new bridged dinuclear complexes (C10H6N2{NHPPh2Ru(eta(6)-benzene)Cl-2}(2)], 1, [C10H6N2{PPh2NHRh(cod)Cl}(2)], 2 and [C10H6N2{NHPPh2Ir(eta(5)-C5Me5)Cl-2}(2)], 3, respectively. All new complexes have been fully characterized by analytical and spectroscopic methods. (HP)-H-1-P-31{H-1} NMR, (HC)-H-1-C-13 HETCOR or (HH)-H-1-H-1 COSY correlation experiments were used to confirm the spectral assignments. 1, 2 and 3 are suitable catalyst precursors for the transfer hydrogenation of acetophenone derivatives. Notably [Ru((Ph2PNH)(2)C10H6N2)(eta(6)-benzene)Cl-2], 1 acts as an excellent catalyst, giving the corresponding alcohols in 98-99% yields in 10 min at 82 degrees C (TOF <= 600 h(-1)) for the transfer hydrogenation reaction in comparison to analogous rhodium or iridium complexes. This transfer hydrogenation is characterized by low reversibility under these conditions. (C) 2012 Elsevier B.V. All rights reserved.Öğe Asymmetric transfer hydrogenation of acetophenone derivatives with novel chiral phosphinite based ?6-p-cymene/ruthenium(II) catalysts(Elsevier Science Sa, 2011) Aydemir, Murat; Meric, Nermin; Baysal, Akin; Turgut, Yilmaz; Kayan, Cezmi; Seker, Sevil; Togrul, MahmutEnantioselective reduction of prochiral ketones to optically active secondary alcohols is an important subject in synthetic organic chemistry because the resulting chiral alcohols are extremely useful, biologically active compounds. The new chiral ligands (2R)-2-[benzyl{(2-((diphenylphosphanyl)oxy)ethyl)}amino]butyldiphenylphosphinite, 1 and (2R)-2-[benzyl{(2-((dicyclohexylphosphanyl)oxy)ethyl)}amino]butyldicyclohexylphosphinite, 2 and the corresponding ruthenium(II) complexes 3 and 4 have been prepared. The structures of these complexes have been elucidated by a combination of multinuclear NMR spectroscopy, IR spectroscopy and elemental analysis. P-31-{H-1} NMR, DEPT, H-1-C-13 HETCOR or H-1-H-1 COSY correlation experiments were used to confirm the spectral assignments. These ruthenium(II) ephosphinite complexes have been used as catalysts for the asymmetric transfer hydrogenation of acetophenone derivatives. Under optimized conditions, aromatic ketones were reduced in good conversions and in moderate to good enantioselectivities (up to 85% ee). (C) 2011 Elsevier B. V. All rights reserved.Öğe Asymmetric transfer hydrogenation of alkyl/aryl or alkyl/methyl ketones catalyzed by known C2-symmetric ferrocenyl-based chiral bis(phosphinite)-Ru(II), Rh(I) and Ir(III) complexes(Elsevier Science Sa, 2016) Durap, Feyyaz; Karakas, Duygu Elma; Ak, Bunyamin; Baysal, Akin; Aydemir, MuratKnown Ru(II), Rh(I) and Ir(III) complexes of C-2-symmetric ferrocenyl based chiral bis(phoshinite) ligands were catalyzed the asymmetric transfer hydrogenation of alkyl/aryl or alkyl methyl ketones. Corresponding secondary alcohols were obtained with high enantioselectivities up to 98% ee and reactivities using iso-propanol as the hydrogen source. (C) 2016 Elsevier B.V. All rights reserved.Öğe Asymmetric transfer hydrogenation of aromatic ketones with the ruthenium(II) catalyst derived from C2 symmetric N,N?-bis[(1S)-1-benzyl-2-O-(diphenylphosphinite)ethyl]ethanediamide(Elsevier Science Sa, 2010) Aydemir, Murat; Meric, Nermin; Durap, Feyyaz; Baysal, Akin; Togrul, MahmutAsymmetric transfer hydrogenation of ketones with chiral molecular catalysts is realized to be one of the most magnificent tools to access chiral alcohols in organic synthesis. A new chiral phosphinite compound N,N'-bis[(1S)-1-benzyl-2-O-(diphenylphosphinite)ethyl]ethanediamide (1), has been synthesized by the reaction of chlorodiphenylphosphine with N,N'-bis[(1S)-1-benzyl-2-hydroxyethyl]ethanediamide under argon atmosphere. The oxidation of 1 with aqueous hydrogen peroxide, elemental sulfur or grey selenium in toluene gave the corresponding oxide 1a, sulfide 1b and selenide 1c, respectively. Pd, Pt and Ru complexes were obtained by the reaction of 1 with [MCl2(cod)] (M: Pd 1d, Pt 1e) and [Ru(p-cymene)Cl-2](2) 1f, respectively. All these new complexes were characterized by using NMR, FT-IR spectroscopies and microanalysis. Additionally, as a demonstration of their catalytic reactivity, the ruthenium complex 1f was tested as catalyst in the asymmetric transfer hydrogenation reactions of acetophenone derivatives with iPrOH was also investigated. (C) 2010 Elsevier B.V. All rights reserved.Öğe Bis(phosphinite) with C2-Symmetric Axis; Effects on the Ruthenium(II)-Catalyzed Asymmetric Transfer Hydrogenation of Acetophenone Derivatives(Georg Thieme Verlag Kg, 2012) Aydemir, Murat; Durap, Feyyaz; Kayan, Cezmi; Baysal, Akin; Turgut, YilmazChiral ruthenium catalyst systems generated in situ from [Ru(eta(6)-p-cymene)(mu-Cl)Cl](2) complex and chiral C-2-symmetric bis(phosphinite) ligands based on amino alcohol derivatives were employed in the asymmetric transfer hydrogenation of aromatic ketones to give the corresponding optically active alcohols in high yield. The best results were obtained in the [Ru(eta(6)-p-cymene)(mu-Cl)Cl](2) and (2S)-2-[benzyl(2-{benzyl[(2S)-1-[(diphenylphosphanyl)oxy]-3-phenyl propan-2-yl]amino}ethyl)amino]-3-phenylpropyl diphenylphosphinite or (2R)-2-[benzyl(2-{benzyl[(2R)-1-[(diphenylphosphanyl) oxy]-3-phenylpropan-2-yl]amino}ethyl) amino]-3-phenylpropyl diphenylphosphinite catalytic systems, which gave enantioselectivities of up to 93% ee and 99% conversion.Öğe Cationic and neutral ruthenium(II) complexes containing both arene or Cp* and functionalized aminophosphines. Application to hydrogenation of aromatic ketones(Elsevier Science Sa, 2010) Aydemir, Murat; Baysal, AkinHydrogen transfer reduction processes are attracting increasing interest from synthetic chemists in view of their operational simplicity. For this aim, a series of novel Ru(II) complexes with the P-N-P ligands were synthesized starting from the complex [Ru(eta 6-p-cymene)(mu-Cl) Cl] 2 or [RuCp*Cl(COD)]. The complexes were fully characterized by analytical and spectroscopic methods. (31)P-{(1)H} NMR, DEPT, (1)H-(13)C HETCOR or (1)H-(1)H COSY correlation experiments were used to confirm the spectral assignments. Complexes 5, 6 and 7 catalyze the transfer hydrogenation of acetophenone derivatives to 1-phenylethanol derivatives in the presence of iso-PrOH as the hydrogen source. Catalytic studies showed that all complexes are excellent catalytic precursors for the transfer hydrogenation of acetophenone derivatives in 0.1 M iso-PrOH solution. Notably 5 acts as an excellent catalyst giving the corresponding alcohols in excellent conversions up to 99% (TOF <= 492 h(-1)). (C) 2010 Elsevier B. V. All rights reserved.Öğe Chiral C2-symmetric ?6-p-cymene-Ru(II)-phosphinite complexes: Synthesis and catalytic activity in asymmetric reduction of aromatic, methyl alkyl and alkyl/aryl ketones(Elsevier Science Sa, 2018) Karakas, Duygu Elma; Aydemir, Murat; Durap, Feyyaz; Baysal, AkinChiral C-2-symmetric bis(phosphinite) ligands and their binuclear ruthenium(II) complexes have been synthesized and used as catalysts in the ruthenium-catalyzed asymmetric transfer hydrogenation of aromatic, methyl alkyl and alkyl/aryl ketones using 2-propanol as both the hydrogen source and solvent in the presence of KOH. Under optimized conditions, all complexes showed high catalytic activity as catalysts in the reduction of various ketones to corresponding chiral secondary alcohols. Products were obtained with high conversions (99%) and moderate to good enantioselectivities (82% ee). Furthermore, C2-symmetric bis(phosphinite) ligands and their binuclear ruthenium(II) complexes were characterized by multinuclear NMR spectroscopy, FT-IR spectroscopy, LC/MS-MS and elemental analysis. (C) 2017 Elsevier B.V. All rights reserved.Öğe Chiral phosphinites as efficient ligands for enantioselective Ru(II), Rh(I) and Ir(III)-catalyzed transfer hydrogenation reactions(Springer, 2017) Baysal, Akin; Karakas, Duygu Elma; Meric, Nermin; Ak, Bunyamin; Aydemir, Murat; Durap, FeyyazMetal-catalyzed enantioselective transfer reduction of ketones to enantiomerically enriched chiral alcohols has recently attracted attention. Therefore, a series of methyl alkyl or alkyl/aryl ketones have been reduced by using Ru(II), Rh(I) and Ir(III) catalysts based on C (2)-symmetric chiral ferrocenyl phosphinite ligands. The corresponding optically active secondary alcohols were obtained in excellent conversions and moderate-to-good enantioselectivities. The best results were obtained with an iridium catalyst, giving up to 98% conversion and 80% ee.Öğe Electrical and photoelectrical characterization of organic-inorganic heterostructures based on Ru-N-heterocyclic carbene complexes(Elsevier Gmbh, 2018) Yasar, Sedat; Cekirdek, Suzan; Binbay, Nil Ertekin; Tombak, Ahmet; Ocak, Yusuf Selim; Arslan, Nevin; Baysal, Akin1,3-Bis(2-morpholinethyl)benzimidazoliumtrichlorido(eta(6)-p-cymene)-ruthenate(11), 2, was synthesized and characterized by NMR spectroscopy and micro analysis. The organic -inorganic heterojunctions were fabricated by using n-type Si wafer and a series of Ru-N-heterocyclic carbene complexes, 3-5, bearing sterically hindered aryl groups were documented for the first time. The thin films of the complexes are deposited on n-Si substrates using spin coating. Current-voltage (I-V) measurements of the devices in dark and illuminated environments were analyzed to determine electrical parameters of devices. Furthermore, the photoelectrical properties of the structures were investigated examined using I-V measurements under a solar simulator. Complexes 3 and 5 showed very low series resistance resulting in high rectification ratios which are promising results for the future electronic and photoelectronic applications. (C) 2017 Published by Elsevier GmbH.Öğe The first application of C2-symmetric ferrocenyl phosphinite ligands for rhodium-catalyzed asymmetric transfer hydrogenation of various ketones(Elsevier Science Sa, 2015) Ak, Bunyamin; Aydemir, Murat; Durap, Feyyaz; Meric, Nermin; Baysal, AkinHomogeneous catalysis has been responsible for many major recent developments in synthetic organic chemistry. The combined use of organometallic and coordination chemistry has produced a number of new and powerful synthetic methods for important classes of compounds in general and for optically active substances in particular. For this aim, a new class of chiral modular C-2-symmetric ferrocenyl phosphinite ligands has been prepared in good yields by using the inexpensive 1,1'-ferrocenedicarboxyaldehyde and various ferrocene based-amino alcohols as starting materials, and applied in the rhodium(I)-catalyzed asymmetric transfer hydrogenation (ATH) of aromatic ketones to give corresponding secondary alcohols with excellent enantioselectivities and reactivities using isoPrOH as the hydrogen source (up to 99% conversion and 99% ee). The substituents on the backbone of the ligands are found to exhibit a remarkable effect on both the activity and % ee. The structures of these ligands and their complexes have been elucidated by a combination of multinuclear NMR spectroscopy, IR spectroscopy and elemental analysis. (C) 2015 Elsevier B.V. All rights reserved.Öğe Froth flotation pretreatment for enhancing desulfurization of coal with sodium hydroxide(Natl Inst Science Communication, 2007) Saydut, Abdurrahman; Tonbul, Yalcin; Baysal, Akin; Zahir Duz, M.; Hamamci, CandanFroth flotation (FF) pretreatment of coal from Hazro, Turkey, for enhancing desulfurization with sodium hydroxide was investigated. FF reduced following contents of coal: ash, 58.54; pyritic sulfur, 79.34; and volatile matter, 56.98%. The coal flotation was 69.59%. FF could not remove organic sulfur Coal concentration obtained from flotation was leached using aqueous NaOH and its organic sulfur content was reduced by 59.27%. Hence using combination of two methods, total sulfur, ash and volatile matter, contents was reduced by 88.06%, 63.13% and 77.32%, respectively.Öğe Influence of Temperature And Light Intensity on Ru(II) Complex Based Organic-Inorganic Device(Amer Inst Physics, 2016) Asubay, Sezai; Durap, Feyyaz; Aydemir, Murat; Ocak, Yusuf Selim; Tombak, Ahmet; Baysal, AkinAn organic-inorganic junction was fabricated by forming [Ru(Cy2PNHCH2-C4H3O)(eta(6)-p-cymene)Cl-2] complex thin film using spin coating technique on n-Si and evaporating Au metal on the film. It was seen that the structure had perfect rectification property. Current-voltage (I-V) measurements were carried out in dark and under various illumination conditions (between 50-100 mW/cm(2)) and with the temperature range from 303 to 380 K. The structure showed unusually forward and reverse bias temperature and light sensing behaviors. It was seen that the current both in forward and reverse bias increased with the increase in light intensity and temperature.Öğe Methyl ester of peanut (Arachis hypogea L.) seed oil as a potential feedstock for biodiesel production(Pergamon-Elsevier Science Ltd, 2009) Kaya, Canan; Hamamci, Candan; Baysal, Akin; Akba, Osman; Erdogan, Sait; Saydut, AbdurrahmanThe peanut (Arachis hypogea L.) seed oil was extracted from the seeds of the peanut that grows in SE Anatolia of Turkey. Oil was obtained in 50 wt/wt.%, by solvent extraction. Peanut (A. hypogea L) seed oil was investigated as an alternative feedstock for the production of a biodiesel fuel. Biodiesel was prepared from peanut by transesterification of the crude oil with methanol in the presence of NaOH as catalyst. A maximum oil to ester conversion was 89%. The viscosity of biodiesel oil is nearer to that of petroleum diesel and the calorific value is about 6% less than that of diesel. Peanut seed oil have about 8.3% less heating value than that of diesel oil due to the oxygen content in their molecules. The quality of biodiesel is most important for engine part of view and various standards have been specified to check the quality. The important properties of peanut oil and its methyl ester (biodiesel) such as density, kinematic viscosity, flash point, iodine number, neutralization number, pour point, cloud point, cetane number are found out and compared to those of no, 2 petroleum diesel, ASTM and EN biodiesel standards. The comparison shows that the methyl ester has relatively closer fuel properties to diesel than that of raw peanut seed oil. (C) 2008 Elsevier Ltd. All rights reserved.Öğe A modular design of ruthenium(II) catalysts with chiral C2-symmetric phosphinite ligands for effective asymmetric transfer hydrogenation of aromatic ketones(Pergamon-Elsevier Science Ltd, 2010) Aydemir, Murat; Meric, Nermin; Baysal, Akin; Gumgum, Bahattin; Togrul, Mahmut; Turgut, YilmazHydrogen-transfer reduction processes are attracting increasing interest from synthetic chemists in view of their operational simplicity. The new chiral C-2-symmetric ligands N,N'-bis-[(1S)-1-sec-butyl-2-O-(diphenylphosphinite)ethyl]ethanediamide, 1 and N,N'-bis-[(1S)-1-phenyl-2-O-(diphenylphosphinite)ethyl]ethanediamide, 2 and the corresponding ruthenium complexes 3 and 4 have been prepared and their structures have been elucidated by a combination of multi-nuclear NMR spectroscopy, IR spectroscopy, and elemental analysis. H-1-P-31 NMR, DEPT, H-1-C-13 HETCOR, or H-1-H-1 COSY correlation experiments were used to confirm the spectral assignments. The catalytic activity of complexes 3 and 4 in transfer hydrogenation of acetophenone derivatives by iso-PrOH has also been studied. Under optimized conditions, these chiral ruthenium complexes serve as catalyst precursors for the asymmetric transfer hydrogenation of acetophenone derivatives in iso-PrOH and act as excellent catalysts, giving the corresponding chiral alcohols in 99% yield and up to 75% ee. This transfer hydrogenation is characterized by low reversibility under these conditions. (C) 2010 Elsevier Ltd. All rights reserved.Öğe New active ruthenium(II) complexes based N3,N3?-bis(diphenylphosphino)-2,2?-bipyridine-3,3?-diamine and P,P?-diphenylphosphinous acid-P,P?-[2,2?-bipyridine]-3,3?-diyl ester ligands for transfer hydrogenation of aromatic ketones by propan-2-ol(Elsevier Science Sa, 2009) Aydemir, Murat; Baysal, Akin; Meric, Nermin; Gumgum, BahattinThe dimeric starting material [Ru(eta(6)-p-cymene)(mu-Cl)Cl](2) reacts with N3,N3'-bis(diphenylphosphino)-2,2'-bipyridine-3,3'-diamine, 1 and P,P'-diphenylphosphinous acid-P,P'-[2,2'-bipyridine]-3,3'-diyl ester, 2 ligands to afford bridged dinuclear complexes [C10H6N2{NHPPh2-Ru(eta(6)-p-cymene)Cl-2}(2)], 3 and [C10H6N2{OPPh2-Ru(eta(6)-p-cymene)Cl-22], 4 in quantitative yields. These bis(aminophosphine) and bis(phosphinite) based Ru(II) complexes serve as active catalyst precursors for the transfer hydrogenation of acetophenone derivatives in 2-propanol and especially 4 acts as a good catalyst, giving the corresponding alcohols in 99% yield in 20 min (TOF <= 280 h(-1)). (C) 2009 Elsevier B.V. All rights reserved.Öğe New C2-symmetric chiral phosphinite ligands based on amino alcohol scaffolds and their use in the ruthenium-catalysed asymmetric transfer hydrogenation of aromatic ketones(Elsevier France-Editions Scientifiques Medicales Elsevier, 2013) Durap, Feyyaz; Aydemir, Murat; Elma, Duygu; Baysal, Akin; Turgut, YilmazAsymmetric transfer hydrogenation processes of ketones with chiral molecular catalysts are attracting increasing interest from synthetic chemists due to their operational simplicity. C-2-symmetric catalysts have also received much attention and been used in many reactions. A series of new chiral C-2-symmetric bis(phosphinite) ligands has been prepared from corresponding amino acid derivated amino alcohols or (R)-2-amino-1-butanol through a three- or four-step procedure. Their structures have been elucidated by a combination of multinuclear NMR spectroscopy, IR spectroscopy and elemental analysis. H-1-P-31 NMR, DEPT, H-1-C-13 HETCOR or H-1-H-1 COSY correlation experiments were used to confirm the spectral assignments. In situ prepared ruthenium catalytic systems were successfully applied to ruthenium-catalyzed asymmetric transfer hydrogenation of acetophenone derivatives by iso-PrOH. Under optimized conditions, these chiral ruthenium catalyst systems serve as catalyst precursors for the asymmetric transfer hydrogenation of acetophenone derivatives in iso-PrOH and act as good catalysts, giving the corresponding optical secondary alcohols in 99% yield and up to 79% ee. (C) 2012 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.Öğe A new efficient bis(phosphinite)-ruthenium(II) catalyst system for the asymmetric transfer hydrogenation of aromatic ketones(Elsevier Science Sa, 2014) Durap, Feyyaz; Aydemir, Murat; Baysal, Akin; Elma, Duygu; Ak, Bunyamin; Turgut, YilmazMany chiral ligands bearing phosphorus donor atoms were developed and applied in the area of metal catalyzed asymmetric catalysis. A new chiral bis(phoshinite) ligand was successfully synthesized from optically active (1S,8S)-3,6-[N-(S)-alpha-phenylethyl] diaza-1,8-diphenoxymethyl-1,8-octanediol in high yield. A ruthenium(II) complex generated in situ from [Ru(eta(6)-p-cymene)(mu-Cl)Cl](2), bis(phosphinite) ligand and KOH acts as an active catalyst for asymmetric transfer hydrogenation (ATH) of acetophenone derivatives in isopropyl alcohol (IPA) as both solvent and hydrogen source. The catalytic reaction proceeds cleanly to give enantiomerically enriched secondary alcohols up to 90% or 89% ee's at 50 or 82 degrees C, respectively. (C) 2013 Elsevier B. V. All rights reserved.Öğe New Pd(II) and Pt(II)-diaminophosphine complexes bearing cyclohexyl or isopropyl moiety: use of Pd(II) complexes as precatalyst in Mizoroki-Heck and Suzuki-Miyaura cross-coupling reactions(Tubitak Scientific & Technological Research Council Turkey, 2015) Aydemir, Murat; Durap, Feyyaz; Baysal, AkinTwo new diaminophosphine ligands, N,N'-bis(dicyclohexylphosphino)-2-(aminomethyl)aniline (1) and N,N'-bis(diisopropylphosphino)-2-(aminomethyl)aniline (2) were synthesized by the reaction of 2-(aminomethyl)aniline with two equivalents of Cy2PCl or (iPr)(2)PCl, respectively. The reactions of 1 and 2 with MCl2 (cod) (M = Pd, Pt; cod = 1,5-cyclooctadiene) yield complexes [cis-Pd(L2PNHC6H4CH2NHPL2)Cl-2] (L = Cy 3, iPr 4) and [cisPt(L2PNHC6H4CH2NHPL2)Cl-2] (L = Cy 5, iPr 6), respectively. The catalytic activity of the palladium complexes was investigated in the Suzuki-Miyaura cross-coupling reaction in the presence of Cs2CO3 as a base. The palladium complexes were also found to be highly active catalysts in the Mizoroki Heck reaction.
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