Abstract 1-Amino-2-methyl-1, 3-pentadienes were treated with dimethyl 1, 2, 4, 5-tetrazine-3, 6-dicarboxylate to give diazatricyclo [2.2. 2.0] octenes and dimethyl 4-methylpyridazine-3, 6- dicarboxylate, the product distribution being largely dependent on the nature of the amino substituent. Under similar conditions the analogous 1-morpholino-1, 3-butadiene afforded dimethyl pyridazine-3, 6-dicarboxylate as the major product. The tricyclic products ...
