Spiro 1-Allyl-4-phenyl-3a,4-dihydrobenzo[f]isoindolininum Derivatives by Base-catalyzed Intramolecular Cyclization.

The base-catalyzed intramolecular cyclization of (dimethyl)- and (diethyl)-(3-phenylprop-2-enyl)(1-phenylhex-5-en-1-yn-3-yl)ammonium and N-(3-phenylprop-2-enyl)-N-(3-phenylprop-2-ynyl)-piperidinium and -morpholinium bromides was used to synthesize 1-allyl-N,N-diethyl-4-phenyl-1,3,3a,4-tetrahydrobenzo[f]isoindol-2-ium, 1-allyl-N,N-dimethyl-4-phenyl-1,3,3a,4-tetrahydrobenzo[f]isoindol-2-ium, 1-allyl-4-phenyl-1,3,3a,4-tetrahydrospiro(benzo[f]isoindole-2,1'-piperidin)-1'-ium, and 1-allyl-4-phenyl-1,3,3a,4-tetrahydrospiro(benzo[f]isoindole-2,4'-morpholin)-4'-ium bromides in high yields. Cyclization was accompanied by side reactions (8−10%). [ABSTRACT FROM AUTHOR]