Studies on the syntheses of heterocyclic compounds. Part CCCXIII. Phenolic oxidative coupling of a dihydroxy-1-phenethyl-1,2,3,4-tetra-hydroisoquinoline

Abstract

The phenolic oxidative coupling of 1,2,3,4-tetrahydro-6-hydroxy-1-(3-hydroxy-2,4-dimethoxyphenethyl)-7-methoxy-2-methylisoquinoline (XV) with potassium ferricyanide gave abnormal products; phenylpropionaldehyde (XVI), dehydro-seco-homoerythrinadienone (XVII), seco-homoerythrinadienone (XVIII) and a quinoline derivative (XIX). Two synthetic routes to the starting diphenolic isoquinoline (XV) are described.