Bimolecular 4+2-cycloaddition reactions of cross conjugated betaines with Electron rich π-systems
作者:Albert Padwa、Steven J. Coats、Mark A. Semones
DOI:10.1016/s0040-4039(00)73920-7
日期:1993.1
Bicyclic anhydro-2-oxo-4-hydroxy-1,3-thiazinium hydroxides undergo 1,4-dipolar cycloadditions with various electron rich pi-systems to give 4+2-cycloadducts which on further heating, extrude carbonyl sulfide producing substituted alpha-pyridones.