THE CHEMISTRY OF INDOLES .79. A NOVEL DIMERIZATION OF 1-HYDROXYINDOLES

1-Hydroxyindoles are sensitive to acids and undergo four types of comp eting reactions; dehydroxylation, nucleophilic substitution, dimerizat ion, and formation of hexacyclic dimer. The direction of the reaction seems to be determined depending on the subtle balance of substrate st ructures, acids, and reaction conditions. Structures of variety of pro ducts are unequivocally determined by X-ray single crystallographic an alyses and chemical correlations.