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Aminophosphine ligands: synthesis, coordination chemistry, and activity of their palladium(II) complexes in Heck and Suzuki cross-coupling reactions
(Springer, 2011) Kayan, Cezmi; Biricik, Nermin; Aydemir, Murat
The reaction of 4-aminodiphenylamine or 2-aminofluorene with two equivalents of PPh2Cl in the presence of Et3N gives new bis(diphenylphosphino) amines N,N-bis(diphenylphosphino)-4-aminodiphenylamine 1 and N, N-bis(diphenylphosphino)-2-aminofluorene 2 in good yields. Oxidation of 1 or 2 with hydrogen peroxide, elemental sulfur or gray selenium affords the corresponding chalcogen derivatives. The palladium and platinum complexes of these P-N-P donor ligands were prepared by the reaction of the bis(phosphino) amines with MCl2(cod) (M = Pd or Pt, cod = cycloocta-1,5-diene). All the new compounds have been characterized by analytical and spectroscopic methods, including H-1-P-31 NMR, H-1-C-13 HETCOR, or H-1-H-1 COSY correlation experiments. The Pd(II) complexes were investigated as catalysts in the Suzuki and Heck reactions; both showed good catalytic activity affording high yields of the desired products.
Aniline based aminophosphine and cationic bis phosphino amine Ru II complexes: Investigation of catalytic activity in transfer hydrogenation of ketones
(Dicle Üniversitesi, 2013) Kayan, Cezmi; Meriç, Nermin; Aydemir, Murat; Baysal, Akın; Temel, Hamdi
Hydrogen transfer reduction processes are attracting increasing interest from synthetic chemists in viewof their operational simplicity. For this aim, a series of Ru II complexes with the NPP and NHP ligandswere synthesized starting from the complex [Ru ?6-p-simen µ-Cl Cl]2. The complexes were fullycharacterized by analytical and spectroscopic methods. Complexes 1-4 catalyze the transfer hydrogenationof a variety of simple alkyl and aryl alkyl ketones to secondary alcohols in the presence of iso-PrOH as thehydrogen source. Notably 3 acts as an excellent catalyst giving the corresponding alcohols in excellentconversions up to 99% TOF:198 h-1
Application of half-sandwich metal-phosphinite compounds to biological activities: Determine the energies of the HOMO and LUMO levels
(Wiley-V C H Verlag Gmbh, 2023) Meriç, Nermin; Rafikova, Khadichakhan; Zazybin, Alexey; Güzel, Remziye; Kayan, Cezmi; Karakas, Duygu Elma; Dündar, Abdurrahman; Aydemir, Murat
Mononuclear transition metal complexes 1-(furan-2-yl)ethyldiphenyl[dichloro(eta(6)-p-cymene)ruthenium(II)]phosphinite, (2), 1-(furan-2-yl)ethyldiphenyl[dichloro(eta(6)-benzene) ruthenium(II)] phosphinite (3), 1-(furan-2-yl)ethyldipheny[chloro(eta(4)-1,5-cyclooctadiene)rhodium(I)]phosphinite (4), 1-(furan-2-yl)ethyldiphenyl[dichloro (eta(5)pentamethylcyclopentadienyl)iridium (III)] phosphinite (5) were synthesized and characterized by microanalysis, infrared, MS, and NMR spectroscopy. The biological activities of the complexes were also tested. Compounds 2 and 5 were the best complexes at DPPH radical scavenging and reducing power activity at 73.27 % and 0.41 at 200 mu g/mL, respectively. The highest antimicrobial activity exhibited by complex 3 as 14 mm inhibition zone against S. aureus. All of the complexes have cleaved the DNA from the double-strand and exhibited three bands on gel electrophoresis. Moreover, cyclic voltammetry studies of the phosphinite complexes were carried out to determine the energies of the HOMO and LUMO levels as well as to estimate their electrochemical and some electronic properties.
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, Mahmut
Enantioselective 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.
Bazı yeni schiff bazı ligandların hazırlanması ve özelliklerinin spektroskopik yöntemlerle incelenmesi
(2016) Kayan, Cezmi; Biricik, Nermin
Schiff bazları ve metal komplekslerinin sentezlenmesi son yıllarda daha da önem kazanmıştır. Bu önem değişik nedenlerden kaynaklanıyor. Bazı biyolojik işlemlerde önemli bir rol oynarlar. Bir çok enzimatik tepkimede araürün olarak oluşurlar. Biyomoleküllerin yapısının ve biyolojik işlemlerin anlaşılmasında biyolojik model olarak kullanılırlar. Endüstride farmasotik amaçlı bazı kimyasal maddelerin, boyarmaddelerin, plastiklerin insektisitlerin (böcek öldürücü) ve fungisitlerin (mantar öldürücü) üretiminde başlangıç maddesi olarak kullanılırlar. Bazı önemli endüstriyel işlemlerde katalizör olarak kullanılmaları hakkında literatürde bir çok çalışma vardır. Bu çalışmada 4,4*-diaminodifenilmetan (4.4'-metilendianilin) ile asetilaseton, 3- kloroasetilaseton, salisilaldehit, benzaldehit. m-tolualdehit etkileştirilerek 5 tane Schiff bazı sentezlendi. Ayrıca, m-fenilendiamin ile 3-okza-1.5-bis(o-karboksaldehitfenoksi)pentan etkileştirilerek makrosiklik bir Schiff bazı sentezlendi. Bu altı yeni ligandın yapıları İR, 'H-NMR. UV-görünür alan spektroskopisi ve element analizi yöntemleriyle aydınlatıldı. Bu ligandların bazı metal kompleksleri sentezlendiyse de yapıları henüz aydınlatılamadı.
Biological assays and theoretical density functional theory calculations of Rh(I), Ir(III), and Ru(II) complexes of chiral phosphinite ligand
(Wiley, 2020) Rafikova, Khadichakhan; Binbay, Nil Ertekin; Meriç, Nermin; Kerimkulova, Aygül; Zazybin, Alexey; Binbay, Veysel; Okumuş, Veysi; Kayan, Cezmi; Işık, Uğur; Aydemir, Murat; 0000-0003-1010-9563; 0000-0002-2488-0378; 0000-0001-8028-2244; 0000-0002-6244-9327
Four metal complexes, IL-OPPh2-Ru-p-cymene (3), IL-OPPh2-Ru-benzene (4), IL-OPPh2-Ir-Cp* (5), IL-OPPh2-Rh-COD (6), have been evaluated for in vitro antioxidant activity such as 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging and reducing power activity. Maximum scavenging activity (71.43%) was obtained with IL-OPPh2-Ru-p-cymene, whereas IL-OPPh2-Rh-COD showed the highest reducing power ability. The complexes were also studied for their antimicrobial activity against three Gram-positive and three Gram-negative bacteria. In addition, DNA binding of the complexes was evaluated using calf thymus DNA. Both Ru(II) complexes exhibited good DNA-binding activity while the other complexes did not have any activity. Furthermore, ab initio quantum calculations of four complexes were also carried out using density functional theory to better understand their chemical behaviors.
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, Yilmaz
Chiral 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.
Boron containing chiral Schiff bases: Synthesis and catalytic activity in asymmetric transfer hydrogenation (ATH) of ketones
(Elsevier, 2020) Pasa, Salih; Arslan, Nevin; Meric, Nermin; Kayan, Cezmi; Bingul, Murat; Durap, Feyyaz; Aydemir, Murat
Asymmetric Transfer Hydrogenation (ATH) has been an attractive way for the reduction of ketones to chiral alcohols. A great number of novel and valuable synthetic pathways have been achived by the combination usage of organometallic and coordination chemistry for the production of important class of compounds and particularly optically active molecules. For this aim, four boron containing Schiff bases were synthesized by the reaction of 4-formylphenylboronic acid with chiral amines. The boron containing structures have been found as stable compounds due to the presence of covalent B-O bonds and thus could be handled in laboratory environment. They were characterized by H-1 NMR and FT-IR spectroscopy and elemental analysis and they were used as catalyst in the transfer hydrogenation of ketones to the related alcohol derivatives with high conversions (up to 99%) and low enantioselectivities (up to 22% ee). (C) 2019 Elsevier B.V. All rights reserved.
Catalysts for the asymmetric transfer hydrogenation of various ketones from [3-[(2S)-2-[(diphenylphosphanyl)oxy]-3-phenoxypropyl]-1-methyl-1H-imidazol-3-ium chloride] and [Ru(?6-arene)(?-Cl)Cl]2, Ir(?5-C5Me5)(?-Cl)Cl]2 or [Rh(?-Cl)(cod)]2
(Elsevier Science Sa, 2019) Meric, Nermin; Arslan, Nevin; Kayan, Cezmi; Rafikov, Khadichakhan; Zazybin, Alexey; Kerimkulova, Aygul; Aydemir, Murat
The combination of [3-[(2S)-2-[(diphenylphosphanyl)oxy]-3-phenoxypropyl]-1-methyl-1H-imidazol-3-ium chloride] with [Ru(eta(6)-arene)(mu-Cl)Cl](2), Ir(eta(5)-C5Me5)(mu-Cl)Cl](2) or [Rh(mu-Cl)(cod)](2), in the presence of KOH/isoPrOH, has been found to generate catalysts that are capable of enantioselectively reducing alkyl, aryl ketones to the corresponding (R)-alcohols. Under optimized conditions, when the catalysts were applied to the asymmetric transfer hydrogenation, we obtained the secondary alcohol products in high conversions and enantioselectivities using only 0.5 mol% catalyst loading. In addition, [3-[(2S)-2-{[(chloro(eta(4)-1,5-cyclooctadiene)rhodium)diphenyl phosphanyl] oxy}-3-phenoxypropyl]-1-methyl-1H-imidazol-3-ium chloride], (6) complex is much more active than the other analogous complexes in the transfer hydrogenation. Catalyst 6 acts as excellent catalysts, giving the corresponding (R)-1-phenyl ethanol in 99% conversion in 30 min (TOF <= 396 h(-1)) and in high enantioselectivity (92% ee).
Cross-coupling reactions in water using ionic liquid-based palladium(II)-phosphinite complexes as outstanding catalysts
(Wiley, 2014) Meriç, Nermin; Aydemir, Murat; Işık, Uğur; Ocak, Yusuf Selim; Rafikova, Khadichakhan; Paşa, Salih; Kayan, Cezmi; Durap, Feyyaz; Temel, Hamdi; Zazybin, Alexey G.; 0000-0003-0899-1948; 0000-0002-6244-9327; 0000-0002-4792-8821
Two new phosphinite ligands based on ionic liquids [(Ph2PO)C7H14N2Cl]Cl (1) and [(Cy2PO)C7H14N2Cl]Cl (2) were synthesized by reaction of 1-(3-chloro-2-hydoxypropyl)-3-methylimidazolium chloride, [C7H15N2OCl]Cl, with one equivalent of chlorodiphenylphosphine or chlorodicyclohexylphosphine, respectively, in anhydrous CH2Cl2 and under argon atmosphere. The reactions of 1 and 2 with MCl2(cod) (M=Pd, Pt; cod=1,5-cyclooctadiene) yield complexes cis-[M([(Ph2PO)C7H14N2Cl]Cl)(2)Cl-2] and cis-[M(Cy2PO)C7H14N2Cl]Cl)(2)Cl-2], respectively. All complexes were isolated as analytically pure substances and characterized using multi-nuclear NMR and infrared spectroscopies and elemental analysis. The catalytic activity of palladium complexes based on ionic liquid phosphinite ligands 1 and 2 was investigated in Suzuki cross-coupling. They show outstanding catalytic activity in coupling of a series of aryl bromides or aryl iodides with phenylboronic acid under the optimized reaction conditions in water. The complexes provide turnover frequencies of 57 600 and 232 800h(-1) in Suzuki coupling reactions of phenylboronic acid with p-bromoacetophenone or p-iodoacetophenone, respectively, which are the highest values ever reported among similar complexes for Suzuki coupling reactions in water as sole solvent in homogeneous catalysis. Furthermore, the palladium complexes were also found to be highly active catalysts in the Heck reaction affording trans-stilbenes. Copyright (c) 2014 John Wiley & Sons, Ltd.
DFT investigation of transtion metals arene compounds with functionalized ionic liquid
(INESEG Yayıncılık, 2022) Meriç, Nermin; Binbay, Nil Ertekin; Kayan, Cezmi; Binbay, Veysel; Aydemir, Murat
Electrochemical properties and theoretical DFT computations have been carried out for the cationic parts of complexes of ionic liquid-based phosphinite, (1A-3A). The effects of the chemical structures of cationic parts of three complexes were examined in relation to the variable property of electron-donating ligands for ruthenium and iridium complexes were determined. Their potential energy surfaces in the ground state, electronic densities, and also frontier orbitals HOMO and LUMO have been obtained via DFT calculations. It has been shown that DFT calculations can successfully be used for exploring electrochemical properties of cations, which includes transition metals. It was revealed that complex 1A is the chemically softest molecule, while complex 2A is the most electrophilic one.
Effect of initial configuration on DFT calculations for transition metal complexes
(Osman SAĞDIÇ, 2019) Binbay, Nil E.; Binbay, Veysel; Aydemir, Murat; Durap, Feyyaz; Meriç, Nermin; Kayan, Cezmi; Arslan, Nevin
Computational methods, which solves the Schrödinger’s equation for molecules, have become an indispensable tool in last decades.And Density Functional Theory is one of the most used, and most effective computational method.Transition Metal complexes, on the other hand, have been being used extensively in many important applications in many fields, suchas chemical catalysts, atomic thin films, and pharmaceutical industry. Applying computational methods to transition metal complexeshas become inevitable to understand better, to control and to design these compounds.As it is known, it is very difficult to handle transition metals computationally, mostly due to near degeneracy in their electronic states.The computational algorithms usually cannot achieve as successive result as they can do for other typical elements, like carbon ornitrogen for instance. Computational methods are needed to be improved for properly deal with transition metal complexes. To findcomputationally cheaper but still effective methods to deal with these complexes is a major challenge.Unlike the analogue calculations, computational methods solve all equations iteratively, so there are major differences between thesetwo calculation types. The starting point in state space (the assumed initial conformation of molecule) is could have a stronger effectthen the expected, on the flow of the iterative solving algorithm of the computational approach.Here we present a comparative study for a Ruthenium complex. We have optimised the molecule several times. Each of the optimisationsstarted from different initial molecular conformations. Then we have compared the result in different ways, like calculation times andminimum energy that had reached, to see effect of starting configurations on the calculation.It is showed that, starting configuration is an important parameter for computational calculations of transition metal complexes, and itis needed to be carefully chosen to improve success of calculations.
Half-sandwich ruthenium(II) and iridium(III) complexes of imidazole based phosphinite ligands: antioxidant and antibacterial activities as well as electrochemical properties
(John Wiley and Sons Inc, 2024) Işık, Uğur; Rafikova, Khadichakhan; Meriç, Nermin; Güzel, Remziye; Kerimkulova, Aygül; Akimbek, Arailym; Okumuş, Veysi; Durap, Feyyaz; Kayan, Cezmi; Aydemir, Murat
Ruthenium(II) and iridium(III) complexes of phosphinites including imidazole moiety were synthesized and characterized by microanalysis, IR, MS, and NMR spectroscopies. Antibacterial activity against Gram-positive and Gram-negative bacterial strains was assessed in all complexes. The highest radical scavenging (72.2 %) was obtained for [3-(3-chloro-2-({[dichloro(η6-benzene)ruthenium]diphenylphosphanyl}oxy)propyl)-1-butyl-1H-imidazol-3-ium chloride], 4 at 200 μg/mL concentration, while [3-(3-chloro-2-({[dichloro(η5-pentamethylcyclopentadienyl)-iridium]diphenylphosphanyl}oxy)pro-pyl)-1-butyl-1H-imidazol-3-ium chloride], 6 demonstrated the highest antibacterial activity as 13 mm inhibition zone against E. hirea. Furthermore, optical and electrochemical featured of metal complexes containing imidazole phosphinite were investigated utilizing UV–vis absorption and cyclic voltammetry techniques. Consequently, all complexes can be proposed as metal-based charge convertible phosphinite complexes which may be employed as new generation and synergistic Dye-Sensitized Solar Cell (DSSC) materials.
İki çekirdekli rutenyum II aren komplekslerinin ketonların transfer hidrojenasyonuna uygulanması
(Dicle Üniversitesi, 2013) Meriç, Nermin; Kayan, Cezmi; Aydemir, Murat; Ocak, Yusuf Selim; Baysal, Akın; Temel, Hamdi
Geçifl metal katalizörlerinin transfer hidrojenasyon reaksiyonuyla organik substratlara hidrojen katılmasıveya çıkarılması önemli bir sentetik araçtır. Bu amaçla, N3,N3'-di-2-hidroksibenziliden-[2,2']bipiridinil3,3'-diamin bilefliğinden elde edilen bir P-O ligandı olan N3,N3'-di-2- difenilfosfino benziliden-[2,2']bipiridinil3,3'-diaminin bir dizi metal kompleksi sentezlendi. N3,N3'-di-2- difenilfosfino benziliden-[2,2']bipiridinil3,3'-diaminin [Ru ?-benzen µ-Cl Cl] yada [Ru ?-p-simen µ-Cl Cl]2 ile reaksiyonu köprülü ve ikiçekirdekli [CH16N4{OPPh2-Ru ?6-benzen Cl2}2] 1 ve [Ckomplekslerini vermektedir. Ru II -bisfosfinit kompleksleri ayrıca basit birçok alkil ve aril alkil ketonuntransfer hidrojenasyonunda katalizör olarak kullanıldı ve iyi düzeyde % 99'a kadar dönüflümler eldeedildi
Imine containing C2-Symmetric chiral half sandwich ?6-p-cymene-Ru(II)- phosphinite complexes: Investigation of their catalytic activity in the asymmetric transfer hydrogenation of ketones
(Elsevier, 2020) Saleh, Najmuldain Abdullah; Pasa, Salih; Kayan, Cezmi; Meric, Nermin; Sunkur, Murat; Aral, Tarik; Aydemir, Murat
New chiral C-2-symmetric bis(phosphinite) ligands containing imine group were synthesized from 1-({[(1R,2R)-2-{[(2-hydroxynaphthalen-1-yl)methylidene] amino}cyclohexyl]- imino}methyl)- naphthalen-2-ol and two equivalents of Ph2PCl, (i-Pr)(2)PCl or (Cy)(2)PCl, in high yields. Binuclear C-2-symmetric half sandwich eta(6)-p-cymene-Ru(II) complexes of the chiral phosphinite ligands were synthesized by treating of [Ru(eta(6)-p-cymene)(mu-Cl)Cl](2) with the phosphinites in 1:1 M ratio in CH2Cl2. Their catalytic activities in asymmetric transfer hydrogenation (ATH) were investigated for the reaction of acetophenone derivatives with isopropyl alcohol. The corresponding optically active secondary alcohols were obtained in excellent levels of conversion (96-99%) and moderate enantioselectivity (up to 60% ee). Among three complexes investigated, complex 4 was the most efficient one. (C) 2019 Elsevier B.V. All rights reserved.
Ketone transfer hydrogenation reactions catalyzed by catalysts based on a phosphinite ligand
(Taylor & Francis, 2022) Rafikova, Khadichakhan; Baysal, Akın; Meriç, Nermin; Zazybin, Alexey; Kayan, Cezmi; Işık, Uğur; Durap, Feyyaz; Aydemir, Murat
Reaction of (+/-)-1-(2-furyl) ethanol with an equivalent Ph2PCl in the presence of Et3N proceeds in dry toluene under an argon atmosphere to give 1-(furan-2-yl)ethyl diphenylphosphinite (1) in good yield. Mononuclear complexes [dichloro(eta(6)-p-cymene)(1-furan-2-ylethyl diphenylphosphinite)ruthenium(II)] (2), [dichloro(eta(6)-benzene)(1-furan-2-ylethyl diphenylphosphinite)ruthenium(II)] (3), [chloro(eta(4)-1,5-cyclooctadiene)(1-furan-2-ylethyl diphenylphosphinite)rhodium(I)] (4) and [dichloro(eta(5)-pentamethylcyclopentadienyl)(1-furan-2-ylethyl diphenylphosphinite)iridium(III)] (5) were synthesized and characterized by microanalysis, infrared, MS, and NMR spectroscopies. The complexes are employed as catalysts in transfer hydrogenation of aromatic ketones. The complexes catalyzed reduction of a variety of aromatic ketone substrates bearing electron-withdrawing or donating substituents with very high conversion rates (up to 99%); 5 was the most efficient catalyst for the transfer hydrogenation of ketones.
Kiral Fosfinit Ligandları Içeren Yeni Rutenyum(II) Komplekslerinin Sentezi ve Ketonların Asimetrik Transfer Hidrojenasyon Reaksiyonundaki Katalitik Aktivitelerinin Arastırılması
(2015) Aydemir, Murat; Karakaplan, Mehmet; Gürbüz, Nevin; Kayan, Cezmi
Etkin kiral fosfor ligandların özellikle kiral iskelet yapısına sahip olanların geliştirilmesine yönelik çalışmalar asimetrik katalizin en öncelikli konuları arasında yeralmaktadır. Gu?nu?mu?ze kadar, fosfin ve metal-fosfin komplekslerinin sentezine yönelik çok çaba harcanmış olmasına rağmen, benzer yapıdaki bis(fosfinitler) yeterince araştırılmamıştır. Fosfin ligandları metal katalizli asimetrik dönu?şu?mlerde oldukça yaygın uygulama alanları bulmuştur. Ancak, fosfinitler fosfinlerle kıyaslandığında farklı kimyasal, elektronik ve yapısal özelliklere sahip olmaları bu ligandları daha da ilgi çekici kılmaktadır. Örneğin, fosfinitlerdeki metal fosfor bağı fosfinlerdeki bağ ile kıyaslandığında, elektron çekici P-OR grubundan dolayı daha gu?çlu?du?r. Ayrıca, fosfinitlerdeki P(OR)R2 boş ?* orbitalinin varlığı, fosfiniti daha iyi bir alıcı konumuna getirerek kararlı duruma getirebilmektedir. Ancak, fosfinitlerin analogları olan fosfinlere göre en bu?yu?k avantajı hazırlanmalarındaki kolaylıktır. İlgili ketonların indirgenmesi sonucu elde edilen kiral sekonder alkoller, ticari açıdan önemli birçok farmasötikler, zirai maddeler, parfu?mler, tatlandırıcılar ve özel materyaller için anahtar konumundaki madde görevi u?stlenir. Asimetrik sentez genellikle çok bu?yu?k miktarlarda nispeten du?şu?k maliyetli kiral u?ru?nler sağlama avantajı nedeniyle en çok dikkat çeken yöntem olarak kabul edilir. Ketonların ilgili kiral alkollere asimetrik dönu?şu?mu? için kullanılan en bilinen yöntemler hidrosililasyon, hidroborasyon, biyoindirgeme ve katalitik (transfer) hidrojenasyon olarak sayılabilir. Bu yöntemde karbonil bileşiklerini ilgili alkollere dönu?ştu?rmek için hidrojen kaynağı olarak sekonder alkoller (2- propanol v.b.) kullanılır. Böylece, moleku?ler hidrojen kullanılması nedeniyle ortaya çıkabilecek patlama riski ortadan kaldırılır. Üstelik bu reaksiyonda kullanılan 2-propanol’ u?n oldukça kararlı, çalışılması kolay, anti-toksik ve ucuz olması da metodun diğer avantajlarındandır. Bu projede; ilk olarak birbirinden farklı kiral bileşiklerden yola çıkılarak regioseçici epoksit halka açılması yöntemiyle kiral amino alkoller hazırlanmıştır. Sonraki basamakta ise kiral aminoalkoller PPh2Cl etkileştirilerek kiral fosfinit tu?revleri sentezlenmiştir. Hazırlanan yeni kiral fosfinit bileşikleri Ru[(?6-p-simen)Cl2]2 ve Ru[(?6-benzen)Cl2]2 ile etkileştirilerek yeni Ru(II) geçiş metal kompleksleri sentezlenmiş ve bu komplekslerin yapıları NMR, IR, LC- ESI-IT-TOF MS ve element analizi ile aydınlatılmıştır. Son olarak elde edilen komplekslerin, ketonların asimetrik transfer hidrojenasyon reaksiyonlarında kiral katalizör olarak kullanımları araştırılmıştır.
New bis(diphenylphosphino)aniline derivatives: Synthesis and spectroscopic characterization
(Wiley-Hindawi, 2007) Biricik, Nermin; Durap, Feyyaz; Kayan, Cezmi; Gümgüm, Bahattin; 0000-0003-0899-1948; 0000-0001-5700-8546
Six new multidentate bis(diphenylphosphino)amine [R-N(PPh2)(2)] ligands have been prepared from the reaction of aniline derivatives, R-NH2, with Ph2PCl in the presence of triethylamine. All of the compounds were obtained in good yields and were characterized by NMR, IR, and microanalysis. (c) 2007 Wiley Periodicals, Inc.
New chiral phosphinite ligands with C2-symmetric axis and their possible applications in Ru-catalyzed asymmetric transfer hydrogenation
(Wiley, 2010) Aydemir, Murat; Meriç, Nermin; Baysal, Akın; Kayan, Cezmi; Toğrul, Mahmut; Gümgüm, Bahattin; 0000-0001-7294-6792; 0000-0001-5700-8546
The new chiral ligands N,N'-bis-[(1R)-1-ethyl-2-O-(diphenylphosphinite)ethyl]ethanediamide, 1, and N,N'-bis-[(1S)-1-isobutyl-2-O-(diphenylphosphinite)ethyl]ethanediamide, 2, and the corresponding ruthenium complexes 3 and 4 were prepared and their structures were elucidated by a combination of multinuclear NMR spectroscopy, IR spectroscopy and elemental analysis. Following activation by NaOH, these chiral ruthenium complexes serve as catalyst precursors for the asymmetric transfer hydrogenation of acetophenone derivatives in iPrOH. The complexes 3 and 4 showed high catalytic activity but low selectivity in asymmetric transfer hydrogenation reactions. Copyright (C) 2009 John Wiley & Sons, Ltd.
New chiral ruthenium(II)-phosphinite complexes containing a ferrocenyl group in enantioselective transfer hydrogenations of aromatic ketones
(Pergamon-Elsevier Science Ltd, 2013) Ak, Bunyamin; Elma, Duygu; Meric, Nermin; Kayan, Cezmi; Isik, Ugur; Aydemir, Murat; Durap, Feyyaz
A new and versatile class of unsymmetrical ferrocenyl-phosphinite ligands possessing a stereogenic center has been prepared from commercially available, inexpensive aminoacids such as, D-, L-phenylglycine and D-, L-phenylalanine, through a concise synthetic procedure. These ligands are not very sensitive to air and moisture, and display good enantioselectivities in the ruthenium-catalyzed asymmetric transfer hydrogenation of acetophenone derivatives, in which up to 91% ee was obtained. A comparison of the catalytic properties of amino alcohols and other analogues based on a ferrocenyl backbone is also discussed briefly. The structures of these ligands and their corresponding complexes have been elucidated by a combination of multinuclear NMR spectroscopy, IR spectroscopy, and elemental analysis. (C) 2013 Elsevier Ltd. All rights reserved.

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