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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Enantioselective Synthesis of Glutarimide Alkaloids Cordiarimides A, B, Crotonimides A, B, and Julocrotine
TL;DR: In this paper, the authors proposed a method to solve the problem of artificial neural networks in the context of artificial intelligence. National Natural Science Foundation of China [20832005], National Basic Research Program (973 Program) of China[2010CB833200]
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Asymmetric synthesis of allylic secondary alcohols: a new general approach for the preparation of α-amino acids
TL;DR: In this paper, a new general approach for the synthesis of optically active α-amino acids has been developed, which involves a ruthenium catalysed cross-coupling reaction to give a range of α,β-unsaturated ketones, which were then reduced to allylic secondary alcohols in the presence of a chiral CBS oxazaborolidine.
Journal ArticleDOI
Synthesis of 15R-PGD2: a potential DP2 receptor agonist.
TL;DR: 15R-PGD(2), a potential DP(2) receptor agonist, could be an important novel tool for defining the role of this receptor in inflammatory diseases.
Journal ArticleDOI
The asymmetric synthesis of both enantiomers of eliprodil
TL;DR: The asymmetric synthesis of both enantiomers of the racemic NMDA antagonist eliprodil was accomplished in a novel application of Sharpless' asymmetric dihydroxylation (AD) methodology, noting a difference in neuroprotective activity in an in vivo model of rat focal cerebral ischemia.
Journal ArticleDOI
Toward the total synthesis of the brasilinolides: construction of a differentially protected C20-C38 segment.
Ian Paterson,Paul M. Burton,Christopher J. Cordier,Michael P. Housden,Friedrich A. Mühlthau,Olivier Loiseleur +5 more
TL;DR: An efficient, convergent synthesis of a differentially protected C20-C38 segment of the brasilinolides is described.
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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