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1.
Asymmetric transfer hydrogenation of ketones catalyzed by rhodium and iridium complexes with chiral bidentate Schiff's bases 总被引:1,自引:0,他引:1
Pavlov V. A. Vinogradov M. G. Starodubtseva E. V. Chel"tsova G. V. Ferapontov V. A. Malyshev O. R. Heise G. L. 《Russian Chemical Bulletin》2001,50(4):734-735
Rhodium and iridium complexes of Schiff's bases derived from (1R,2R)- and (1S,2S)-diaminocyclohexane catalyze asymmetric transfer hydrogenation of alkyl aryl ketones in PriOH at room temperature to give chiral secondary alcohols (up to 65% ee). 相似文献
2.
Jean-Thomas Issenhuth Samuel Dagorne Stéphane Bellemin-Laponnaz 《Comptes Rendus Chimie》2010,13(3):353-357
The CuCl/NaOt-Bu/BINAP system was found to efficiently catalyze the hydrosilylation of aryl alkyl ketones with excellent enantioselectivities by using phenyl methyl silane as a stoichiometric hydride source. High enantiomeric excesses (up to 97%) and excellent yields (up to 99%) were obtained. 相似文献
3.
Grazia Zassinovich Clorinda del Bianco Giovanni Mestroni 《Journal of organometallic chemistry》1981,222(2):323-329
The reduction of prochiral ketones by hydrogen transfer from isopropanol is catalyzed by cationic iridium(I) complexes containing optically active Schiff bases. Optical yields of up to 33% have been obtained. 相似文献
4.
Renato Sariego Irma Carkovic Manuel Martínez Mauricio Valderrama 《Transition Metal Chemistry》1984,9(3):106-108
Summary Hydrogen transfer reactions from 2-propanol to acetophenone or cyclohexene are catalyzed by neutral rhodium(I) complexes of the type [Rh(COD)L] and [Rh2(COD)2L] (where L and L are Schiff base ligands and COD=cycloocta-1,5-diene). Some dependency of the catalytic activity on the electronic and steric properties of the ligands are discussed. 相似文献
5.
In the presence of 20 mol% of chiral catalytic complex prepared from In(OTf)3 and chiral PYBOX, allyltributylstannane reacted with achiral ketones to afford the corresponding homoallylic alcohols in moderate to high enantioselectivities (54-95% ee), which constitutes the first example of enantioselective allylation of ketones catalyzed by the chiral In(III)-PYBOX complex. 相似文献
6.
7.
Yong-Chul Jeong 《Tetrahedron letters》2004,45(50):9249-9252
Sterically hindered chiral Schiff base ligands 4a-d were prepared from an aldehyde derived from BINOL. The vanadium complexes of the ligands catalyze an efficient, enantioselective H2O2-promoted sulfoxidation of alkyl aryl sulfides, and enantioselectivities as high as 98-99% ee are observed in the sulfoxidation of benzyl aryl sulfides. 相似文献
8.
R. Spogliarich A. Tencich J. Kaspar M. Graziani 《Journal of organometallic chemistry》1982,240(4):453-459
The reduction of ketones and olefins by hydrogen transfer from isopropanol is catalyzed by tertiary phosphine complexes of rhodium and iridium. The influence of the nature of the ligands and of the reaction conditions on the catalytic activity has been investigated. The reduction of the carbonyl group in the presence of olefins is also reported. 相似文献
9.
铱(I)联萘胺Schiff碱(BPMBNDI)配合物催化苯乙酮的不对称氢转移反应 总被引:5,自引:0,他引:5
用旋光活性2, 2'-(1, 1'-联萘)二胺和2-吡啶基甲醛缩合得到的Schiff碱BPMBNDI[N, N'-二(2-吡啶基亚甲基)-(1, 1'-联萘)-2, 2'-二亚胺]为配体与[Ir(COD)Cl]2(COD=1, 5-环辛二烯)反应, 生成了10个光学活性铱配合物。研究它们在异丙醇对苯乙酮不对称氢转移反应中的光学诱导活性时, 发现10个催化剂均具有较高的立体选择性,其中[Ir(COD)(BPMBNDI)I]催化的光学产率高达84%。 相似文献
10.
Nevin Arslan 《Phosphorus, sulfur, and silicon and the related elements》2020,195(8):628-637
AbstractThe interaction of [Ru(η6-arene)(μ-Cl)Cl]2 and Ir(η5-C5Me5)(μ-Cl)Cl]2 with a new Ionic Liquid-based phosphinite ligand, [(Ph2PO)-C6H9N2Ph]Cl, (2) gave [Ru((Ph2PO)-C6H9N2Ph)(η6-p-cymene)Cl2]Cl (3), [Ru((Ph2PO)-C6H9N2Ph)(benzene)Cl2]Cl (4) and [Ir((Ph2PO)-C6H9N2Ph)(C5Me5)Cl2]Cl (5), complexes. All the compounds were characterized by a combination of multinuclear NMR and IR spectroscopy as well as elemental analysis. Furthermore, the Ru(II) and Ir(III) catalysts were applied to asymmetric transfer hydrogenation of acetophenone derivatives using 2-propanol as a hydrogen source. The results showed that the corresponding alcohols could be obtained with good activity (up to 55% ee and 99% conversion) under mild conditions. Notably, [Ir((Ph2PO)-C6H9N2Ph)(C5Me5)Cl2]Cl (5) is more active than the other analogous complexes in the transfer hydrogenation (up to 81% ee). 相似文献
11.
Manoj K. Pandey 《Tetrahedron letters》2006,47(6):897-900
The catalytic, enantioselective carbonyl-ene reaction of ethyl glyoxylate with α-methylstyrene and 4-halo-α-methylstyrene has been investigated in the presence of copper triflate-bisoxazoline complexes. The reaction proceeded smoothly to give γ,δ-unsaturated-α-hydroxy esters in moderate to good yields and with excellent enantioselectivity (up to 100% ee). A hypothesis has been provided to explain the reversal of enantioselectivity in the reaction. 相似文献
12.
《Journal of organometallic chemistry》1986,302(2):265-267
The complexes formed in situ from Ir(COD)acac and chiral menthylphenylphosphines proved to be active catalysts in the hydrogen transfer reaction from isopropanol to prochiral ketones. When acetophenone was used, optical yields of up to 42% were achieved, the configuration of the carbinols being dependent on the bulkiness of the phosphine employed. Concerning the reaction rate, the activation process and the P/Ir ratio, the two menthyl-substituted phenylphosphines display different behaviour. 相似文献
13.
14.
Manabu Hatano 《Tetrahedron letters》2007,48(49):8590-8594
The enantioselective conjugate addition of dialkylzinc (R2Zn) to cyclic enones was examined using chiral binaphthyldiamine-copper(I) catalysts. Under the present reaction conditions, chiral C2-symmetric [RZn(II)]2-diamine-Cu(I) complexes were formed from chiral binaphthyldiamine, R2Zn, and copper(I or II) chloride in situ. The reaction of 2-cyclohexenone with Et2Zn proceeded smoothly in the presence of the corresponding chiral copper(I) complex (5 mol %) and achiral 2,6-diphenylaniline (10 mol %), and the desired Et-adduct was obtained with up to 76% ee in 95% yield. 相似文献
15.
《Journal of organometallic chemistry》1986,306(3):407-412
The asymmetric hydrogen transfer from propan-2-ol to prochiral ketones is effectively catalyzed by diphosphine complexes of iridium and rhodium. The influence of the reaction conditions on the activity and selectivity of the catalysts has been investigated. 相似文献
16.
The stereoselective addition of phenyl acetylene and alkyl acetylenes to imines, catalyzed by chiral bis-imines-Cu(I) complexes was studied. A very simple experimental procedure allowed to obtain at room temperature optically active propargyl amines in very good yields and enantioselectivity up to 81%. 相似文献
17.
Iridium-based asymmetric reduction of ketones to chiral enantiomerically enriched alcohols has recently attracted attention by a number of research groups and interest in this area is growing. This review presents the different catalytic systems based on iridium complexes that have been used in asymmetric hydrosilylation, in asymmetric transfer hydrogenation (ATH) with alcohols or formic acid derivatives as reducing agents, and in asymmetric hydrogenation (H2 as reducing agent). A large variety of chiral ligands of various denticities and bearing various combination of coordinating atoms (N, P, S, O, C, …) have been used and will be presented. The last part critically reviews the mechanistic understanding of all the above transformations with specific reference to iridium catalysts. 相似文献
18.
Cesar A. Madrigal 《Journal of organometallic chemistry》2008,693(15):2535-2540
The catalytic activity in asymmetric transfer hydrogenation of ketones using octahedral and half-sandwich (η5-indenyl and η6-arene) ruthenium(II) complexes containing the chiral ligand (4S)-2-[(Sp)-2-(diphenylphosphino)ferrocenyl]-4-(isopropyl)oxazoline (FcPN) has been explored. Catalytic studies with complex fac-[RuCl2{η2(P,N)-FcPN}(PMe3)2] (1) show excellent TOF values (9600 h−1). Experiments in the presence of free FcPN, which lead to an increase in conversion rates and ee values when the catalyst is complex [Ru(η5-C9H7){κ2(P,N)-FcPN}(PPh3)][PF6] (4) have been carried out. The characterization of the new complexes mer-trans-[RuCl2{P(OMe)3}2{κ2(P,N)-FcPN}] and of the water-soluble complexes fac- and mer-trans-[RuCl2(PTA)2{κ2(P,N)-FcPN}] is also reported. 相似文献
19.
The detailed catalytic mechanisms on transfer hydrogenation of ketones are explored by employing the representative reaction of 3-pentanone and 2-propanol catalyzed by the model complex IrH3[(Me2PC2H4)2NH], derived from the catalyst IrH3[(iPr2PC2H4)2NH], with the aid of the density functional theory calculations. The geometrical transformation from an octahedron to a Y-type involved in the catalytic cycle is also elucidated in terms of molecular theory of transition metal complexes. The trend for the variation of Ir-N bond distance is also analyzed. 相似文献
20.
《Tetrahedron: Asymmetry》2000,11(6):1367-1374
The catalytic enantioselective reduction of aromatic ketones in 2-propanol is carried out by using ruthenium(II) complexes prepared from [Ru(p-cymene)Cl2]2 and a variety of chiral diamines and β-aminoalcohols derived from α-amino acids. Good conversions (>99%) and enantioselectivities (=96%) are observed under mild reaction conditions. 相似文献