Metalation of Hantzsch Esters and Mixed Amide Esters: A General Route to C-2 Functionalized 1,4-Dihydropyridines

Article abstract of DOI:10.1021/jo00067a012

1,4-Dihydropyridine (Hantzsch) diesters 3a-e readily undergo metalation at the C-2 methyl (vinylogous ester) position on treatment with alkyllithium bases.The resulting anion intermediates can be treated with electrophilic reagents to afford 1,4-dihydropy