SUBSTITUTED 1-THIA-3-AZA -1,3-BUTADIENE: DIELS-ALDER REACTION WITH METHYLACRYLATE. DETERMINATION OF ACTIVATION PARAMETERS

Abstract
2-Phenyl-4-dimethylamino-1-thia-3-azabutadiene and methylacrylate gave 5,6-dihydro-4H-1,3-thiazine by 4 + 2 cyclocondensation reaction at 55°C. The heterodienes configuration was established by X-Ray spectra. The Diels-Alder character of this reversible reaction was indicated by kinetic and thermodynamic parameters determined by 1H N.M.R.