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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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Cobalt-catalyzed asymmetric hydroboration of aryl ketones with pinacolborane.
Jun Guo,Jianhui Chen,Zhan Lu +2 more
TL;DR: The highly enantioselective cobalt-catalyzed hydroboration reaction of aryl ketones with HBpin was developed using iminopyridine oxazoline ligands, demonstrating its synthetic advantage.
Journal ArticleDOI
Der Stand der Totalsynthese zu Beginn des 21. Jahrhunderts
TL;DR: In this article, the authors stellten die Frage, welchen Stand die Totalsynthese von Naturstoffen erreicht hat, und geschildert, wie viel wir in der Wissenschaft der Totalsynthesis schon erreich haben, aber also, dass dieses Forschungsgebiet den Kinderschuhen gerade erst entschlupft.
Journal ArticleDOI
A new process for the enantioselective synthesis of chiral α-aryloxy- and α-hydroxy acids
E. J. Corey,John O. Link +1 more
TL;DR: Chiral trichloromethyl carbinols 3 were converted with inversion of configuration into chiral α-aryloxy and α-hydroxy carboxylic acid derivatives.
Journal ArticleDOI
Recent advances in the synthetic applications of the oxazaborolidine-mediated asymmetric reduction
Journal ArticleDOI
Enantioselective bromolactonization of cis-1,2-disubstituted olefinic acids using an amino-thiocarbamate catalyst
TL;DR: A facile, highly regio- and enantioselective amino-thiocarbamate-catalyzed bromolactonization of cis-1,2-disubstituted olefinic acids has been developed and the use of the enantio-enriched lactones in the synthesis of chiral synthetic intermediates is demonstrated.
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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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