Studies on the syntheses of heterocyclic compounds. Part CCCXCII. An alternative total synthesis of petaline
Abstract
Petaline (1) was synthesised by methylation of 1,2,3,4-tetrahydro-8-hydroxy-7-methoxy-1-(4-methoxybenzyl)-2-methylisoquinoline (12) prepared from 5-benzyloxy-2-bromo-4-methoxyphenethylamine (5) by two methods. Moreover, tetrahydroisoquinoline (12) was synthesised by Stevens reaction of 8-benzyloxy-1,2,3,4-tetrahydro-7-methoxy-2-(4-methoxybenzyl)isoquinoline methochloride (21).