Aqueous base induced selective transformations of 3-(2-oxoalkyl) thiazolium cations

Article abstract of DOI:10.1016/S0040-4020(01)81227-8

The title compounds react with aqueous sodium hydroxide (i) 2%, 1 equiv., (ii) 2%, 2 equiv., and (iii) 8%, 2 equiv., to give 2-hydroxy-2-alkyl/aryl-4-formyl-2,3-dihydro-1,4-thiazines (7), 2-alkyl/aryl-4-formyl-1,4-thiazines (8) and 2-aroylthiazoles (9), r