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
Computational educidation of the catalytic mechanism for ketone reduction by an oxazaborolidine–borane adduct
TL;DR: The reaction pathway around the complete catalytic cycle for THF-borane reduction of propanone catalysed by the oxazaborolidine form (S)-proline has been determined by AM1 semiepirical MO calculations, including characterisation of all transition structures.
Journal ArticleDOI
Asymmetric oxazaborolidine-catalyzed reduction of prochiral ketones with N-tert-butyl-N-trimethylsilylamine–borane
TL;DR: In this paper, the oxazaborolidine-catalyzed reduction of representative aryl and aliphatic ketones was carried out obtaining the corresponding alcohols in 83.89% isolated yields and 69.98% ee.
Journal ArticleDOI
Stereospecificity of the Au(I)-catalyzed reaction of 1-alkynyl-bicyclo[4.1.0]-heptan-2-ones with nucleophiles
TL;DR: In this article, the stereospecificity of the Au(I)-catalyzed reaction of 1-alkynyl-bicyclo[4.1.0]-heptan-2-ones with nucleophiles was investigated.
Journal ArticleDOI
Optimization of orally bioavailable alkyl amine renin inhibitors
Zhenrong Xu,Salvacion Cacatian,Jing Yuan,Robert D. Simpson,Lanqi Jia,Wei Zhao,Colin M. Tice,Patrick T. Flaherty,Joan Guo,Ishchenko Alexey,Suresh B. Singh,Zhongren Wu,Brian M. McKeever,Boyd B. Scott,Yuri Bukhtiyarov,Jennifer Berbaum,Jennifer M. Mason,Reshma Panemangalore,Maria Grazia Cappiello,Ross Bentley,Christopher P. Doe,Richard K. Harrison,Gerard McGeehan,Lawrence W. Dillard,Baldwin John J,David A. Claremon +25 more
TL;DR: Lead compound 21a, has an IC(50) of 0.83nM for the inhibition of human renin in plasma (PRA), and oral administration of 21a at 10mg/kg resulted in >20h reduction of blood pressure in a double transgenic rat model of hypertension.
Journal ArticleDOI
Enantioselective catalytic borane reductions of achiral ketones : synthesis and application of new chiral β-amino alcohols from L-methionine
T. Mehler,Jürgen Martens +1 more
TL;DR: In this article, the in situ formed chiral oxazaborolidine catalysts from optically active β-amino alcohols 1-3 from L-methionine ethyl carboxylate 4 have been used successfully in the enantioselective catalytic homogenous borane reductions of various aromatic ketones.
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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