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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The control of remote asymmetric centres via reduction of acyclic carbonyl functions
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David A. Evans,Percy H. Carter,Erick M. Carreira,André B. Charette,Joëlle Prunet,Mark Lautens +5 more
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Diastereoselective transformation of chiral η6-Arene-Cr(CO)3 complexes: Enantioselective synthesis of functionalized hydronaphthalene derivatives related to the seco-pseudopterosins
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Total synthesis and structure–activity relationship study of the potent cAMP signaling agonist (−)-alotaketal A
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Overview: PAF Receptor Antagonists: Recent Advances
TL;DR: In this paper, the PAF Receptor Antagonists: Recent Advances were discussed. But they focused on PAF receptor antagonists and did not consider PAF receptor antagonists.
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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