In 1700 ml of dichloromethane was suspended 180.0 g of 5,6-dimethoxy-1-(1-trityl-4-imidazolyl)methyl-1H-indazole-3-methanol, having been ground to powder in a mortar, at room temperature, followed by stirring while cooling with ice. To the reaction mixture was added dropwise 48.6 ml of thionyl chloride over 5 minutes. One minute later, the spot of the starting material on a thin layer chromatogram (chloroform:ethanol=30:1) disappeared. The reaction mixture was poured into 2000 ml of a saturated sodium hydrogencarbonate aqueous solution and extracted with 5000 ml of chloroform. The extract was dried over sodium sulfate, filtered, and the solvent was evaporated to yield 165.1 g of a colorless solid. This solid was used in the subsequent reaction without further purification.
