The reaction of imidazo[1,5-a]pyridines with methyl- and phenyltriazolinediones and with diethyl azodicarboxylate

Imidazo[1,5-a]pyridines react in one of two ways with methyl- and phenyl triazolinediones and diethyl azodicarboxylate to give either Michael type addition products at C-3 or C-1, or novel 1,2,4-triazolines. The nature of the product depends upon the dienophile and the substitution pattern of the imidazo[1,5-a]pyridine.