Reactions of pyridinium ylides with aldehydes and with Michael acceptors

Abstract

1 -Methyl and 1 -allyl-2,4,6-triphenylpyridinium cations react with aromatic aldehydes at the a-CH2 to give aldol products ( 7) and ( 8). The allyl adducts (8) were thermally converted into aldehydes and ketones, whereas thermolysis of (7) took a variety of courses. Zwitterions from 1 -methylpyridinium cations were also added Michael-fashion to activated carbon-carbon double bonds.