Reactions of 2-[(2-arylimino-2-cyano-1,1-dimethylethyl)arylamino]-3-methylbut-2-enenitrile with copper(II) acetate:: synthesis of 2-(2,3-dihydro-2,2-dimethyl-3-oxo-1H-indol-1-yl)-3-methylbut-2-enenitriles

Treatment of 2-[(2-arylimino-2-cyano-1,1-dimethylethyl)arylamino]-3-methylbut-2-enenitrile 15, prepared by reactions of N-aryl alpha-cyanoenamines 3 with Cu(OAc)(2).H2O (2 equiv.) in the presence of pyridine (2 equiv.) in EtOH at reflux, and with Cu(OAc)(2).H2O (1 equiv.) in HOAc at reflux gave 2-(2,3-dihydro-2,2-dimethyl-3-oxo-1H-indol-1-yl)-3-methylbut-2-enenitriles 11 in moderate to good yields.