Phenolic cyclisation. Part X. Isoquinoline cyclisation under basic conditions

Abstract

The treatment of 3-hydroxy-N-methylphenethylamine (5) with benzaldehyde, 4-chlorobenzaldehyde, phenylpropionaldehyde, cyclohexanone, and cyclopentanone in ethanol afforded the corresponding 1-aryl- and 1-spirocyloalkano-1,2,3,4-tetrahydro-2-methylisoquinolines(7), (8), (9), (11), and (12), respectively. Furthermore, the above isoquinoline cyclisation was found to occur in basic media such as pyridine and triethylamine.