Asymmetric transfer hydrogenation of 1-phenyl dihydroisoquinolines using Ru(II) diamine catalysts
摘要:
A new [Ru(II)(eta(6)-p-cymene)(1R,2R)-N-((1S,2S)-borneol-10-sulfonyl)-1,2-diphenylethylenediamine] catalyst for the asymmetric transfer hydrogenation of both 1-alkyl and 1-aryl dihydroisoquinolines has been isolated. For the first time in this type of reaction, the catalyst employs an N-alkylsulfonyl group instead of N-arylsulfonyl. (c) 2013 Elsevier B.V. All rights reserved.
The Ru-catalyzed enantioselective preparation of chiral halohydrins and their application in the synthesis of (R)-clorprenaline and (S)-sotalol
摘要:
The asymmetric transfer hydrogenation of a series of halo-substituted aryl methyl ketones, including those substituted in both alpha-methyl and aryl rings, was studied for the preparation of chiral halohydrins. Up to 99.7% ee was obtained with 2-chloro-1-(2-chlorophenyl)ethanone as the substrate and Ru-CsDPEN as the catalyst in an HCOONa/H2O system. (R)-Clorprenaline, a drug used in the treatment of respiratory disorders, such as bronchitis and asthma, and (S)-sotalol, a class-III antiarrhythmic compound, were prepared with these chiral halohydrins. (C) 2011 Elsevier Ltd. All rights reserved.