By reaction of methyl vinyl ketone (A) with 1,7,8,12b-tetrahydrobenzo[1,2] cyclohepta[3,4,5-d,e]isoquinoline hydrochloride (I) at 100 C to give trans-1,2,4,4a,8,9,13b,14-octahydro-3H-benzo[6,7]cyclopenta[1,2,3-d,e]pyrido[2,1-a]isoquinolin-3-one (II), m.p. 163-5 C, which is alkylated with tert-butyllithium in benzene.