Coreximine and Related Compounds. I. : A Synthesis of O-Demethylcoreximine under Eschweiler-Clarke's Conditions : Studies on the Syntheses of Heterocyclic Compounds. CLXII.

Abstract

7-Benzyloxy-1-(3, 4-bisbenzyloxybenzyl)-6-methoxy-1, 2, 3, 4-tetrahydroisoquinoline (XIV) was submitted to the Eschweiler-Clarke reaction in 98% formic acid and 37% formaldehyde solution, and 7-benzyloxy-1-(3, 4-bisbenzyloxybenzyl)-6-methoxy-2-methyl-1, 2, 3, 4-tetrahydroisoquinoline (XV) was obtained in 5.9% yield, with trans-2, 10, 11-trisbenzyloxy-3-methoxy-5, 6, 13, 13a-tetrahydro-8H-dibenzo-[a, g] quinolizine (XVI) in 80.4% yield. XVI was also obtained in 83.1% yield by refluxing XIV in a mixture of acetic acid and 37% formaldehyde solution, and dehydrogenation of XVI with mercuric acetate gave a quarternary ammonium salt (XIX). Debenzylation of XVI in ethanolic hydrochloric acid gave (±)-O-demethylcoreximine (XVII) whose methylation with diazomethane gave (±)-norcoralydine (XVIII), which was identified with an authentic sample through admixture, infrared spectra, and by thinlayer chromatography.