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
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Ir(ppy)3-Catalyzed, Visible-Light-Mediated Reaction of α-Chloro Cinnamates with Enol Acetates: An Apparent Halogen Paradox
TL;DR: The visible-light-mediated activation of vinyl chlorides derived from α-chloro ethyl cinnamates via oxidative quenching of excited photocatalyst fac-Ir(ppy)3 is described, giving rise to synthetically useful 1,4-dicarbonyl compounds in good to excellent yields.
Journal ArticleDOI
On the synthesis of cepacin A
Chao-Jun Tang,Yikang Wu +1 more
TL;DR: In this article, the diyne moiety was incorporated into the molecular framework through a coupling of the TMS protected diyne with a proper bromoallene under the Sonogashira conditions with EtOAc as the solvent.
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Unconventional Macrocyclizations in Natural Product Synthesis.
TL;DR: This Outlook focuses on a selection of examples employing what the authors term unconventional macrocyclizations toward the synthesis of natural products or analogues.
Journal ArticleDOI
The protecting-group directed diastereoselective Nozaki–Hiyama–Kishi (NHK) reaction: total synthesis and biological evaluation of zeaenol, 7-epi-zeaenol and its analogues
Debendra K. Mohapatra,Debendra K. Mohapatra,D. Sai Reddy,D. Sai Reddy,N. Arjunreddy Mallampudi,Janardhan Gaddam,Janardhan Gaddam,Sowjanya Polepalli,Nishant Jain,J. S. Yadav,J. S. Yadav +10 more
TL;DR: The most suitable protecting groups with respect to selectivity during the protecting group directed intermolecular asymmetric Nozaki-Hiyama-Kishi reaction are observed.
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A new class of bradykinin 1 receptor antagonists containing the piperidine acetic acid tetralin core.
Christopher H. Fotsch,Gloria Biddlecome,Kaustav Biswas,Jian Jeff Chen,Derin C. D'amico,Robert D. Groneberg,Nianhe Bruce Han,Feng-Yin Hsieh,Augustus Kamassah,Gondi N. Kumar,Dianna Lester-Zeiner,Qingyian Liu,David A. Mareska,Babak Riahi,Yueh-Ju Judy Wang,Kevin Yang,James Zhan,Joe Zhu,Eileen Johnson,Gordon Ng,Benny C. Askew +20 more
TL;DR: A new class of B1 receptor antagonists that contain the piperidine acetic acid tetralin core are described, and one of these compounds shows modest oral bioavailability in rats.
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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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