Rhodium(I)-Catalyzed Enantioselective Ring-Opening and Isomerization of Cyclobutanols through a (Z)-Unsaturated Ketone Intermediate

Authors：Lu, Jianzhong; Zhang, Mengzhen; Zheng, Xinxin; Shen, Pei; Xu, Yuemeng; Zhang, Qian; Tang, Yixin; Zhang, Guozhu^*; Guo, Rui^*

Source：Organic Letters, 2023, 25(27): 5151-5156.

DOI：10.1021/acs.orglett.3c01870

• ASYMMETRIC HYDROGENATION
• 4+2 CYCLOADDITION
• RHODIUM
• CLEAVAGE
• CONSTRUCTION
• ACCESS
• ADDITIONS
• ALKYNES
• SHIFT
• ACIDS

A rhodium(I)-catalyzedhighly enantioselective ring-opening andisomerization of cyclobutanols has been developed. The reaction providesa mild, atom-economical, and redox-neutral approach for the synthesisof chiral acyclic ketones bearing a & beta;-tertiary stereocenter.Excellent enantioselectivities and high yields can be achieved usingcyclobutanols with alkoxy substituents at the C3 position. Mechanisticstudies reveal that cyclobutanol only undergoes intramolecular hydrogenmigration, and the formation of a (Z)-unsaturatedketone intermediate is crucial for achieving high enantioselectivity.