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
Lewis Acids as Activators in CBS‐Catalysed Diels–Alder Reactions: Distortion Induced Lewis Acidity Enhancement of SnCl4
TL;DR: A correlation was found between the Δδ((2) H) values and rate constants kDA, which indicates a direct translation of Lewis acidity into reactivity of the Lewis acid-CBS complexes.
Journal ArticleDOI
Synthesis and bioactivity of Luffarin I.
Aitor Urosa,Isidro S. Marcos,David Díez,Anna M. Lithgow,Gabriela B. Plata,José M. Padrón,Pilar Basabe +6 more
TL;DR: The first synthesis of Luffarin I, sesterterpenolide isolated from sponge Luffariella geometrica, has been accomplished from commercially available sclareol and showed antiproliferative activities in the range 12–17 μM.
Journal ArticleDOI
Synthesis of a new C(2)-symmetric chiral catalyst and its application in the catalytic asymmetric borane reduction of prochiral ketones.
TL;DR: A new C(2)-symmetric chiral catalyst 3,5-bis[(2S)-(hydroxy-diphenylmethyl)- pyrrolidin-1-ylmethyl]-1,3,4-oxadiazole was successfully synthesized and applied to the catalytic asymmetric reduction of prochiral ketones with borane.
Journal ArticleDOI
Preparation of tricyclic imidazopyridines by asymmetric ketone hydrogenation in the presence of RuCl2[(S)-Xyl-P-Phos][(S)-DAIPEN]
TL;DR: RuCl 2 [PP]-Noyori catalysts were used for the asymmetric reduction of a variety of prochiral ketones possessing an imidazo[1,2-a ]pyridine scaffold as mentioned in this paper.
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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