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Published on: July 28, 2022
Rhodium(I)-Catalyzed Enantioselective Ring-Opening and Isomerization of Cyclobutanols through a (Z)-Unsaturated
Jianzhong Lu1, Mengzhen Zhang1, Xinxin Zheng2
1CCNU-uOttawa Joint Research Centre, Key Laboratory of Pesticides and Chemical Biology Ministry of Education, International Joint Research Center for Intelligent Biosensing Technology and Health, College of Chemistry, Central China Normal University (CCNU), Wuhan, Hubei 430079, P. R. China.
Abstract:
A rhodium(I)-catalyzed highly enantioselective ring-opening and isomerization of cyclobutanols has been developed. The reaction provides a mild, atom-economical, and redox-neutral approach for the synthesis of chiral acyclic ketones bearing a β-tertiary stereocenter. Excellent enantioselectivities and high yields can be achieved using cyclobutanols with alkoxy substituents at the C3 position. Mechanistic studies reveal that cyclobutanol only undergoes intramolecular hydrogen migration, and the formation of a (Z)-unsaturated ketone intermediate is crucial for achieving high enantioselectivity.
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