Dietmar Schomburg, Paul B. Hopkins, W.N. Lipscomb, E.J.Corey, J. Org. Chem. 1980, 45, 1546-1547
O - Haloanilines react with ketone enolate ions in ammonia under irradiation to form indoles in good yields.
A 1972 review on the synthesis of indoles describes some 30 methods, and others have been reported since. We now report a new method that is also novel in principle. It involves SRN1 replacement of halogen from an o-haloaniline by a ketone enolate nicleophile and subsequent cyclization.