Metalation of biginelli compounds: A general unprecedented route to C-6 functionalized 4-aryl-3,4-dihydropyrimidinones

4-Aryl-6-methyl-3,4-dihydro-2(1H)-pyrimidinone esters (DHPMs) readily undergo metalation at the C-6 methyl position on treatment with lithium diisopropylamide at -10 degree Celsius. The resulting anion intermediates could be treated with electrophilic reagents to afford functionalized DHPMs that are chemically elaborated mainly at the C-6 position.