Journal ArticleDOI
A stable and easily prepared catalyst for the enantioselective reduction of ketones. Applications to multistep syntheses
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TLDR
In this paper, the authors described a new method for the catalytic enantioselective reduction of ketones to chiral secondary alcohols, where the stoichiometric reagent in the reduction is borane and the catalyst is a chiral oxazaborolidine such as 1 (0.05-0.1 molfmol of ketone).Abstract:
We have recently described a new method for the catalytic enantioselective reduction of ketones to chiral secondary alcohols.' The stoichiometric reagent in the reduction is borane (usually 0.6 molfmol of ketone), and the catalyst is a chiral oxazaborolidine such as 1 (0.05-0.1 molfmol of ketone). Excellent enantioselectivities, easy recoverability of the chiral catalyst predecessor, near quantitative yields, short reaction times (a few minutes at 23 \"C), and predictability of the absolute configuration of the product contribute to the outstanding utility of this (CBS') process. This paper reports several subsequent developments in this area with respect to improved practicality and important applications. In contrast to 1 which is both air and moisture sensitive, the B-methylated oxazaborolidine 2 can be stored in closed containers at room temperature and weighed or transferred in air. Catalyst 2 is also much more easily prepared than 1. Reaction of (S)-read more
Citations
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Journal ArticleDOI
Erste atrop‐enantioselektive Ringöffnung achiraler Lacton‐verbrückter Biaryle mit chiralen Boranabgeleiteten Hydridübertragungsreagentien
Gerhard Bringmann,Thomas Hartung +1 more
Patent
Injectable depot formulation comprising crystals of iloperidone
TL;DR: An injectable depot formulation comprising crystals having Structure (I) wherein R is (FII) and the X5o value of the crystals is from 1 to 200 microns is presented in this article.
Patent
Enantioselective reduction of ketones
TL;DR: Chiral 1,3,2-oxazaborolidines and tetrahydro-1, 3, 2-oxaborines are effective catalysts for the borane reduction of prochiral ketones to optically active alcohols as discussed by the authors.
Journal ArticleDOI
Enantioselective reduction of ketones by borane catalysed by oxazaphospholidine oxides
TL;DR: In this paper, enantioselective catalysts for the asymmetric reduction of ketones by borane are described; these compounds increase sensitively the reduction rate of numerous ketones and induce ee's up to 94% in the case of the 2-chloroacetophenone.
Journal ArticleDOI
Recent trends in organocatalyzed asymmetric reduction of prochiral ketones
TL;DR: In this article, the authors focused on selected studies on the development of organocatalysts which are classified into six major categories: i) oxazaborolidine, ii) hydroxyamide, iii) BINOL, iv) ionic liquid, v) phosphoric acid and vi) thiourea-amine based catalysts for asymmetric reduction of prochiral ketones.
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Book
Molybdenum and Molybdenum-Containing Enzymes
TL;DR: In this article, a few moment to read a book even only few pages is recommended, even if it is not obligation and force for everybody, reading book becomes a choice of your different characteristics.
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Reduction of Carbonyl Compounds with Chiral Oxazaborolidine Catalysts: A New Paradigm for Enantioselective Catalysis and a Powerful New Synthetic Method.
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