Angamuthu V, Chang WJ, Hou DR. Anti-addition of Dimethylsulfoxonium Methylide to Acyclic α,β-Unsaturated Ketones and Its Application in Formal Synthesis of an Eicosanoid.
ACS OMEGA 2017;
2:4088-4099. [PMID:
31457710 PMCID:
PMC6641733 DOI:
10.1021/acsomega.7b00663]
[Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Accepted: 07/07/2017] [Indexed: 06/10/2023]
Abstract
Cyclopropanation using dimethylsulfoxonium methylide (Corey-Chaykovsky reaction) was examined with a series of linear α,β-unsaturated ketones, and the results showed that the major trajectory for the addition of the sulfur ylide to the enones is anti, related to the γ-substituent. The stereochemical assignment for the generated cyclopropanes was achieved by X-ray crystallography or comparing with the reported spectroscopic data. We found that the diastereoselectivity was influenced by several factors, including the protecting groups, solvents, and temperatures, and good anti/syn ratios (>10:1) were often obtained using the tert-butyldimethylsilyl and tert-butyldiphenylsilyl-protected substrates. The method was applied to a formal synthesis of a natural eicosanoid with good efficiency.
Collapse