Remote Chiral Induction in Vinyl Sulfonium Salt-Mediated Ring Expansion of Hemiaminals into Epoxide-Fused Azepines
作者:Muhammad Yar、Matthew G. Unthank、Eoghan M. McGarrigle、Varinder K. Aggarwal
DOI:10.1002/asia.201000817
日期:2011.2.1
The planet of the azepines: Epoxy‐fused azepines have been synthesized in a highly selective reaction with hemiaminals and vinyl sulfonium salts. Stereochemistry is controlled by the substituent at the four‐ or five‐position of the hemiaminal. The key step involves ring‐opening of the hemiaminal, conjugate addition onto a vinyl sulfonium salt, and epoxidation of the aldehyde by the in situ formed sulfur