Interaction of hydrazides of 2-aryl-4-methyl-4-cyclohexene-1,1-dicarboxylic acids with certain heterocyclic aldehydes

Monohydrazides of 2-aryl-4-methyl-4-cyclohexene-1,1-dicarboxylic acids react with 2-thiophene-, 3-pyridine-, and 4-pyridinecarbaldehydes to form the corresponding acylhydrazones of hydrazides of mono- or dicarboxylic acids of the cyclohexene series depending on the temperature.