A Multifield Study on Dimethyl Acetylenedicarboxylate: A Reagent Able to Build a New Cycle on Diaminoimidazoles

Abstract

A new effective method for the synthesis of imidazo[1,5-b]pyridazines derivatives (yields = 68–89%) by the interaction of 1,2-diamino-4-phenylimidazole with DMAD, in methanol and in the presence of a catalytic amount of acetic acid, is proposed. The course of reaction has been examined by classical organic methods, HPLC-MS analysis, and quantum-chemical calculations.

Keywords

• dimethyl acetylenedicarboxylate
• imidazo[1,5-<i>b</i>]pyridazines
• DFT calculations