Studies on the syntheses of heterocyclic compounds. Part 687. Asymmetric synthesis of salsolidine

Abstract

Syntheses of optically active salsolidine (8) were achieved by reduction of optically active N-alkyl-3,4-dihydro-6,7-dimethoxyisoquinolinium iodides (6b–e) with sodium borohydride, followed by hydrogenolysis of the resulting optically active N-alkylsalsolidines (7b–e) over 10% palladium hydroxide–charcoal. The optical purities of the salsolidine samples obtained were in the range of 15–44%.