Reactions of Dialkyl Chloroethynylphosphonates with Acid Bishydrazides

Abstract Bishydrazides of a series of aliphatic and aromatic dicarboxylic acids were obtained. Their reaction with dialkyl chloroethynylphosphonate enabled the synthesis of new alkyl(phenyl)bis-1,3,4-oxadiazoles. It was shown that the reaction proceeds under mild conditions, does not require the use of catalysts, and affords exclusively the target products with high chemo- and regioselectivity.