The electrochemical oxidation of aromatic ethers. Part 12. The anodic oxidation of 1,4-dihydro-6,7-dimethoxy-4-(3,4-dimethoxybenzyl)-2-methylisoquinolin -3(2H)-one and attempts to synthesise 2-acyl-4-benzyl-1,2,3,4-tetrahydroisoquinolines through the C-4 alkylation of tricarbonyl η6-1,2,3,4-tetrahydroisoquinoline chromium (0) complexes

Article abstract of DOI:10.1016/S0040-4020(01)89448-5

We have reinvestigated the anodic oxidation of 1,4-dihydro-6,7-dimethoxy-4-(3,4-dimethoxybenzyl)-2-methylisoquinolin -3(2H)-one and found it to yield a new product: 2,3,7,9-tetramethoxy-11-(N-methylacetamido)dibenzo[a,e]cycloheptatrie n-5-one. In order to investigate reactions of this type 2-acyl-6,7-dimethoxy-4-(3,4-dimethoxybenzyl)-1,2,3,4-tetrahydroisoqui nolines were required. Attempts to synthesise these compounds from the chromium tricarbonyl complexes of 2-acyl-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinolines have failed, leading instead to 2-acyl-1,4-dibenzyl-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinolines.