The preparation of some benzo-4, 5 and 6-membered mononitrogen heterocycles by cyclisation of an aryne with a side chain carbanion α to a cyanide group has been investigated: Thus 1-cyano-2-methyl-1, 2, 3, 4-tetrahydroisoquinoline,(50%); 4-cyano-1-ethyl- 1, 2, 3, 4-tetrahydroquinoline,(11%) 2-methylisoindole,(89%) have been prepared. Attempts to prepare an N-acetyl indoline gave 2-methylbenzoxazole, and a benzazetine approach ...
