The reaction of 1-(dichloromethyl)-5-nitroisoquinoline with 2-nitropro
pane anion which gives 1-isopropylidenemethyl-5-nitroisoquinoline as m
ajor product is shown to proceed by the consecutive S(RN)1 and E(RC)1
mechanisms. These mechanisms are confirmed by the inhibitory effects o
f dioxygen, p-dinitrobenzene, cupric chloride and TEMPO.