The Biginelli product dihydropyrimidinones (DHPMs) and their derivatives have enormous
biological significance. This article describes the exploration of 2-chloro-1-methylpyridinium
iodide (CMPI) reagent for the development of an environmentally safe, solvent-free
protocol to construct the functionalized 3,4-dihydropyrimidin-2(1H)-ones/thiones. The protocol involves the three-component condensation reaction of
β-keto ester, aldehyde, and urea or thiourea at elevated temperature. The key advantages
of the protocol are its capacity to provide both environmental and economic benefits
owing to its solvent-free conditions, short reaction times, simple workup, and good
to excellent isolated yield of DHPMs.
Keywords
Biginelli reaction - CMPI - 3,4-dihydropyrimidin-2(1
H)-ones/thiones (DHPMs) - one-pot condensation - tri-component reaction