We developed an efficient, easily available, and easy to use proline amide-based ruthenium(II) catalysts for the asymmetric hydride transfer reduction of prochiral ketones and e.e.s up to 98.8% have been measured.
Various ligands for the ruthenium-catalyzed enantioselective reduction of ketones in water have been investigated. Multi-substrate reactions have been carried out for the comparison of various proline amides and aminoalcohol ligands. Two sets of six aromatic ketones have been selected in order to evaluate the enantiomeric excesses of all the resulting alcohols by a single chromatographic analysis.
Synthesis and characterization of new chiral Rh(I) complexes with N, N′-, and N, P-ligands. A study of anchoring on the moodified zeolites and catalytic properties of heterogenized complexes
作者:A. Carmona、A. Corma、M. Iglesias、A. San José、F. Sánchez
DOI:10.1016/0022-328x(94)05195-h
日期:1995.4
Novel chiral bidentate N, N′- and N, P- donors and their rhodium complexes were synthesised and characterized. The reactions of [Rh(COD)Cl}2] and [RhCl(PPh3)3] with different prepared chiral ligands: if(S)-1-L-2-t-butylaminocarbonylpyrrolidine(1a, 1b), (S)-1-L-2-diphenylphosphinomethylpyrrolidine (2a, 2b), (S)-1-L-2-(1-naphthylaminocarbonyl)pyrrolidine (5a, 5b), (S)-1-L-2-(1-naphthylaminomethyl)pyrrolidine
Small organic molecule catalyzed enantioselective direct aldol reaction in water
作者:Swapandeep Singh Chimni、Dinesh Mahajan
DOI:10.1016/j.tetasy.2006.07.016
日期:2006.8
Protonated pyrrolidine based small organic molecules have been designed and evaluated for the asymmetric direct aldol reaction in water. The designed organocatalysts are multifunctional in nature and exploit the combined effect of hydrogen bonding and hydrophobic interactions for enantioselective catalysis in water. As a result a unique direct asymmetric aldol reaction in water catalyzed by a small organic molecule having an amide linkage has been developed. The developed catalyst affords chiral beta-hydroxyketones in good yields (93%) and enantioselectivities (upto 62%) in water. (c) 2006 Elsevier Ltd. All rights reserved.
Enantioselective Synthesis of Binaphthol Derivatives by Oxidative Coupling of Naphthol Derivatives Catalyzed by Chiral Diamine·Copper Complexes
作者:Makoto Nakajima、Irie Miyoshi、Kumiko Kanayama、Shun-ichi Hashimoto、Masahiro Noji、Kenji Koga
DOI:10.1021/jo981808t
日期:1999.4.1
A highly efficient process of aerobic oxidative coupling of 2-naphthol derivatives catalyzed by 1 mol % of Cu(OH)Cl.TMEDA has been developed, Enantioselective oxidative coupling of naphthols was achieved by the use of 10 mol % of chiral catalysts prepared from proline-derived diamines and cuprous chloride, affording the corresponding binaphthols in good enantioselectivities of up to 78% ee. The ester moiety at the 3-position of the substrate was found to be essential for the good asymmetric induction observed in the present coupling reaction.