One-Pot Synthesis of 1H-Indazole-4,7-diols via Iodine(III)-Mediated [3+2] Cyclization in Water

An efficient route in one-pot to a new class of 1 H -indazole-4,7-diols derivatives has been developed through [3+2] cycloadditive approach in water. The cycloaddition reaction was carried out via condensation of phenol and diazomethyl benzene intermediates by taking advantage of iodobenzene diacetate as an oxidant. Eighteen indazole derivatives were successfully prepared by the established method.