Two novel indole rearrangements
Abstract
Ethyl 3-methylindole-2-carboxylate is rearranged by sulphuryl chloride to ethyl 3-methyl-2-oxoindoline-3-carboxylate, and similar transformations accompanied by halogenation are effected by bromine, or ethyl NN-dichlorocarbamate, in aqueous acetic acid. The last reagent converted both NN-dimethylindole-2- and -3-carboxamides into 3,5,7-trichloro-NN-dimethyl-2-oxoindoline-3-carboxamide.