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Updated: Aug 9, 2026

Versatile CO2 Transformations into Complex Products: A One-pot Two-step Strategy
Published on: November 9, 2019
The conformational bias of aryl, arylsulfonyl geminally substituted tertiary carbon centers: applications in
Jeremy P Scott1, Peter R Mullens, Sarah E Brewer
1Department of Process Research, Merck Sharp & Dohme Research Laboratories, Hoddesdon, Hertfordshire, UK. jeremy_scott@merck.com
Abstract:
Intramolecular nitrile oxide-olefin cycloaddition to form hexahydrobenzisoxazole 14, which engenders a phenylsulfonyl, 2,5-difluorophenyl geminally substituted carbon substructure, proceeds with up to 99% ds. A rationalization of the high level of substrate-based stereo-induction observed in this and related ketone and acrylonitrile metallohydride reductions, supported by single crystal X-ray crystallography, is presented.
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