Electrochemical oxidation of aromatic ethers. Part 7. Oxidation of 4-(3,4-dimethoxybenzyl)-6,7-dimethoxy-2-methyl-1,4-dihydro-3(2H)-isoquinolone and related compounds

Abstract

The electrochemical and chemical oxidations of 4-(3,4-dimethoxybenzyl)-6,7-dimethoxy-2-methyl-1,4-dihydro-3(2H)-isoquinolone fail to yield an intramolecularly coupled product, yet the corresponding lactone 4-(3,4-dimethoxybenzyl)-6,7-dimethoxyisochromanone affords both intramolecularly and intermolecularly coupled structures. Some aspects of the mechanism of these reactions are considered and attempts to synthesise isomorphinandienones are described.