PREPARATION AND DIELS-ALDER REACTION OF N-CARBOMETHOXY-5-ETHYL-1,2-DIHYDROPYRIDINE: AN APPROACH FOR THE SYNTHESIS OF CATHARANTHINE

Article abstract of DOI:10.1016/S0040-4039(00)88060-0

N-carbomethoxy-5-ethyl-1,2-dihydropyridine (1) may be prepared by the bromination of N-carbomethoxy-3-ethyl-1,2,5,6-tetrahydropyridine (10), and subsequvent double dehydrobromination with EtAlCl2/HMPA; this diene undergoes Diels-Alder reaction with dimethyl methylenemalonate (2) to give the isoquinuclidine (3), an intermediate in our planned approach to catharanthine.