PREPARATION OF NEW NITROGEN-BRIDGED HETEROCYCLES .43. SYNTHESIS AND REACTION OF 5AH-PYRIDO [1,2-D][1,3,4] THIADIAZEPINE DERIVATIVES

Reactions of some 1-pyridinio- and 1-(4-methylpyridinio)(arenethiocarb onyl) with dimethyl acetylenedicarboxylate in chloroform afforded neit her the expected dimethyl ido-[1,2-d][1,3,4]thiadiazepine-4,5-dicarbox ylates nor their intramolecular Diels-Alder adducts, but gave novel re arranged products, dimethyl .2.0(2,7)]undeca-3,8,10-triene-6,11-dicarb oxylates in low to moderate yields. On the other hand, similar reactio ns of 1-(3-methylpyridinio)- and 1-(2-methylquinolinio)(arenethiocarbo nyl)amidates with the same reagent provided 1:1 primary adducts, dimet hyl rido[1,2-d][1,3,4]thiadiazepine-4,5-dicarboxylates and dimethyl ad iazepino[4,5-alpha]quinoline-4,5-dicarboxylates, respectively.