Imidazol-2-and-4-ylidene by decarboxylation. Studies on the cross-conjugated mesomeric betaine-alkaloid norzooanemonine and its pseudo-cross-conjugated isomer
Abstract
1,3-Dimethylimidazolium-2-carboxylate and -4-carboxylate (norzooanemonine), which belong to two distinct classes of heterocyclic mesomeric