Simple method for the preparation of 1-substituted isatins

The use of potassium carbonate in dimethylformamide (DMF) makes it possible to carry out the N-alkylation of isatins with alkyl bromides and iodides and acyl chlorides at room temperature and with alkyl chlorides at elevated temperatures (70–80 °C) without ring opening. The previously inaccessible N-(2-chloroethyl)-isatins were obtained by alkylation of isatin with 1,2-dichloroethane. The condensation of isatins with 1,3-dichloro-2-butene takes place only at the chlorine atom in the allyl position of the latter.Translated from Khimiya Geterotsiklicheskikh Soedinenii, No. 3, pp. 353–355, March, 1983.