Novel and Efficient Synthesis of DHPMs Catalyzed by di‐DACH‐Pyridylamide Ligands

Abstract

Di‐DACH‐pyridylamide ligands, symmetrical bridged bis‐Schiff base, and spiro pyrrolizines as catalysts in the synthesis of dihydropyrimidinethiones (DHPMs) using the Biginelli reaction is first reported. This new protocol has the advantages of environmental friendliness, short reaction time, excellent yields, and simple post‐treatment procedure. A series of DHPMs were obtained in high yields (up to 98%) in only 6 h. Moreover, based on the optimized condition, a novel Biginelli‐like reaction was first developed.

Catalytic role in Biginelli reaction: Synthesis and biological property studies of 2‐oxo/thioxo‐1,2,3,4‐tetrahydropyrimidines

“…This method needs a short reaction time, environmental friendliness, a simple posttreatment procedure, and excellent yields. [ 60 ] Through the use of titanium‐tetrachloride immobilized on MBA‐cross linked PNVP, PNVP/TiCl 4 , Ali Rahmatpour and Ghazaleh Donyapeyma created an efficient and sustainable method to synthesize 2‐oxo/thioxo‐1,2,3,4‐tetrahydropyrimidines in a single pot using a variety of substituted‐aromatic aldehydes, ethyl‐acetoacetate, and urea/thiourea in ideal circumstances with outstanding to exceptional yields. The catalyst was shown to be temperature‐resistant, quickly manufactured and recovered, able to be used up to five times with acceptable efficiency, and to be stored without losing its catalytic activity for at least 6 months.…”