When 1 - benzyl Reissert compound of isoquinoline was hyrogenationed under high pressure using Raney Ni(w-2) as catalyst, two new hydrogenated products were isolated. They were characterized and confirmed by chemical and spectroscopic analysis to be 1 - iminomethyl -1- benozyl -1,2- dihydroisoquinoline (4) and 3 -phenyl- 10b - benzyl- 1, 10b - dihydroimdazo [5,1-a] isoquinoline (5). From the experimental results a reaction sequece of high pressure catalytic hydrogenation of 1-benzyl Reissert compoud of isoquinoline is proposed and the mechanism of benzoyl migration during high prssure catalytic hydrogenation of Reissert compound of isoquinoline is also discussed. In an attempt to prpare 1 -cyclohexyl Reissert compound of isoquinoline (2b) using cyclohexyl bromide as alkylating agent in the presence of sodium hydride, the product, tured out to be 1- cyanoisoquinoline (1,in 75% yield).

Key words: ISOQUINOLINE P, HYDROGENATION, CATALYTIC REACTION, ALKYLATING AGENT