An efficient synthesis of benzene fused six-,seven- and eight-membered rings containing nitrogen and sulfur by benzyne ring closure reaction

摘要

3,4-Dihydro-2-#-benzo[l,4]thiazines (3a-c),2,3,4,5-tetrahydro[b]-[l,4]thiazapines (3d-f) and 2,3,4,5-tetrahydro-2H-benzo[b][l,4]thiazocines (3g-i) were prepared by the cyclization of the respective 2-bromophenylsulfanyl derivatives of ethylamine (la-c),propylamine (2d-f) and butylamine (2g-i).