CO-CYCLIZATIONS OF NITROGEN-CONTAINING ACETYLENES INDUCED BY A NICKELTRIPHENYLPHOSPHINE COMPLEX TO GIVE AMINOINDANE, ISOINDOLINE AND ISOINDOLINONE DERIVATIVES

N-Methyl-, N,N-dimethyl-, N,N-diethylprop-2-ynylamines, N-prop-2-ynyla cetamide and N-prop-2-ynylbenzamide are co-cyclized with diethyl hepta -1,6-diyne-4,4-dicarboxylate at room temperature in the presence of st oichiometric nickel(o) to give amino- and amido-indanes in fair to goo d yields. The structure;of the product from N-prop-2-ynylbenzamide was established by X-ray crystallography, Likewise, N-alkyldiprop-2-ynyla mines co-cyclize with methyl prop-2-ynyl ether to give isoindolines al beit in lower yields; the corresponding reaction of short chain N-alky nylalknamides requires heating to 60 degrees C but gives isoindolinone s and a 1,4-dihydroisoquinolin-3(2H)-one as mixtures of regioisomers i n good yields, Attempts to synthesize medium-ring, benzo-fused lactams by this method failed.