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A stable and easily prepared catalyst for the enantioselective reduction of ketones. Applications to multistep syntheses
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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
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Synthesis of asymmetric iron–pybox complexes and their application to aziridine forming reactions
Mark Redlich,M. Mahmun Hossain +1 more
TL;DR: In this paper, the synthesis of a series of iron-pybox complexes and their employment in the catalytic asymmetric aziridine forming reaction is presented. But their performance is limited.
Journal ArticleDOI
An Enantioselective Synthetic Route to Atractyligenin Using the Oxazaborolidine-Catalyzed Reduction of β-Silyl- or β-Stannyl-Substituted α,β-Enones as a Key Step
TL;DR: In this article, the authors describe a catalytic enanti-selective synthetic route to the bicyclic tetraene ester 3, a key intermediate for the synthesis of the naturally occurring adenosine diphosphate transport inhibitor atractyligenin.
Journal ArticleDOI
Structure-activity relationship of optically active 2-(3-pyridyl)thiazolidin-4-ones as a PAF antagonists
You Tanabe,Gohu Suzukamo,Y. Komuro,N. Imanishi,S. Morooka,M. Enomoto,A. Kojima,Yuzuru Sanemitsu,Masato Mizutani +8 more
TL;DR: Two sets of optically active 5-substituted 2-(3-pyridyl)thiazolidin-4-ones, highly potent and selective antagonists of platelet activating factor (PAF), displayed apparently different anti-PAF activities between their enantiomers as mentioned in this paper.
Journal ArticleDOI
A polymer-enlarged homogeneously soluble oxazaborolidine catalyst for the asymmetric reduction of ketones by borane
TL;DR: A polymer-enlarged homogeneously soluble oxazaborolidine catalyst has been prepared and used in the enantioselective borane reduction of ketones as discussed by the authors.
Journal ArticleDOI
A short and efficient enantioselective route to a key intermediate for the total synthesis of forskolin
TL;DR: In this paper, a simple enantioselective synthesis of key intermediates for the total synthesis of forskolin has been developed starting from acid 6 and (S)-alcohol 5.
References
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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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