Arthur G. Schultz and William K. Hagmann, J. Org. Chem., Vol. 43, No. 17, 1978
The methodology presented here represents the first report of N-unsubstituted indole preparation by photochemical means. We consider photocyclization of 2-anilinoacetoacetates to be a useful alternative to the traditional Bischler indoles synthesis. Carbon-carbon bond formation occurs in the absence of strong acids, and, in contrast to the Bischler synthesis, electron deficient aniline derivates give indoles in high yield. It should be noted that indole-2-carboxylic esters may be hydrolyzed and decarboxylated on treatment with copper chromite in quinoline.
