Silica sulfuric acid: an efficient catalyst for the synthesis of substituted indazoles

A simple extremely fast and efficient approach for the synthesis of substituted indazole in good to excellent yield catalyzed by using silica sulfuric acid (SSA) in DMSO solvent at room temperature. This is solid state reaction have been attracting the synthetic organic chemist as they provided enhance reaction rates, less environmental pollution, greater selectivity, cleaner products and manipulative simplicity. Various indazoles are obtained in moderate to excellent yield.