OXIDATION OF 1-ACYLINDOLES WITH MOLYBDENUM PEROXO COMPLEX (MoO<sub>5</sub>·HMPA): PREPARATION OF 1-ACYL-<i>trans</i>- AND<i>cis</i>-2,3-DIHYDROXYINDOLINE DERIVATIVES
Oxidation of 1-acylindoles with MoO5·HMPA in methanol gave a mixture of 1-acyl-trans- and cis-2,3-dihydroxyindoline derivatives in good yields, while 1-acyl-2-substituted indole was oxidized to a corresponding 2-hydroxyindoxyl.