3H‐Indol‐3‐ols by a novel ring contraction

Treatment of α‐hydroxy‐α‐phenyl‐o‐toluidide with phosphorus tribromide afforded a series of 4H‐3,1‐benzoxazines. These last, when reacted with potassium amide in liquid ammonia, ring contracted to 2,3‐disubstituted 3H‐indol‐3‐ols. The scope of this rearrangement was examined. The indolols on treatment with hot base were found to rearrange to indoxyls. Several of these as well as their N‐alkylation products are described.