CuH-Catalyzed Enantioselective 1,2-Reductions of α,β-Unsaturated Ketones
作者:Ralph Moser、Žarko V. Bošković、Christopher S. Crowe、Bruce H. Lipshutz
DOI:10.1021/ja102689e
日期:2010.6.16
The first study on a general technology for arriving at valued nonracemic allylic alcohols using asymmetricligand-acceleratedcatalysis by copper hydride is described.
描述了使用氢化铜的不对称配体加速催化获得有价值的非外消旋烯丙醇的通用技术的第一项研究。
Method for producing 1-menthol
申请人:Takasago International Corporation
公开号:US06342644B1
公开(公告)日:2002-01-29
Provided is a method for the production of 1-menthol, which comprises hydrogenation of piperitenone with a transition metal complex of a specified optically active phosphine to produce pulegone, hydrogenation of the obtained pulegone with a ruthenium-phosphine-amine complex in the presence of base to obtain pulegol, and further hydrogenation of the pulegol with a transition metal catalyst.
The Ru(II)-BINAP-1,2-diphenylethylenediamine combined catalyst system effects asymmetric hydrogenation of certain cyclic enones in 2-propanol containing KOH with a substrate/catalyst molar ratio of 250 to 2500. The hydrogenation occurs selectively at the C=O function with excellent enantio- or diastereoselectivity.
Lanthanoids in organic synthesis. 6. Reduction of .alpha.-enones by sodium borohydride in the presence of lanthanoid chlorides: synthetic and mechanistic aspects
作者:Andre L. Gemal、Jean Louis Luche
DOI:10.1021/ja00408a029
日期:1981.9
Eco-friendly stereoselective reduction of α,β-unsaturated carbonyl compounds by Er(OTf)3/NaBH4 in 2-MeTHF
An operationally simple and environmentally benign catalytic procedure has been developed to selectively reduce different alpha,beta-unsaturated ketones. The corresponding allylic alcohols are obtained with high chemo- and diastereoselectivity using Er(OTf)(3) and NaBH4 in 2-MeTHF. This protocol reduces the amount of catalyst and NaBH4 needed, compared to classical procedures and the stages of extraction/purification are carried out in aqueous solutions avoiding the use of toxic solvents. Taking into account that Er(OTf)(3) can be considered even less toxic than table salt and the 'greenness' of 2-MeTHF as a solvent, the system Er(OTf)(3)/2-MeTHF can be proposed as a cheap, efficient, and environmentally sustainable reduction system for the synthesis of allylic alcohols. (C) 2014 Elsevier Ltd. All rights reserved.