Synthetic Study of Emetine and Its Allied Compounds. VIII

Syntheses of bisbenzoquinolizine. (III) Synthesis of 6-piperidyl-(2′)-4′, 5′-methylenedioxy-3, 4, 5, 6, 7, 8-hexahydro-(2′, 1′:1, 2-benzoquinolizine)

Abstract

2, 3′-Dipyridyl and β-3, 4-methylenedioxyphenetyl bromide gave only one addition product of 1:1 under any working conditions so far tevted. From the weak basicity of α-substituted pyridines, the constitution of the product should be β-(pyridyl-α)-pyridine-3, 4-methylenedioxyphenetyl bromide. This substance was readily oxidized to the corresponding pyridone derivative by means of alkaline K₃Fe(CN)₆. Ring-closure followed by hydrogenation gave 6-piperidyl-2′1′-(2′) 4′, 5′-methylenedioxy-3, 4, 5, 6, 7, 8-hexahydro-(2′1′:1, 2-benzoquinolizine), which was identified only by its crystalline Pt-salt.