反应详情

To a mixture of 5-iodo-1H-indazole (0.90 g, 3.69 mmol) and DHP (1.57 g, 18.7 mmol) in dry dichloromethane (20 mL), was added PTSA (0.08 g, 0.41 mmol) at room temperature. The resulting mixture was stirred overnight. Upon completion, saturated aqueous NaHCO3 (30 mL) was added slowly into the reaction mixture. The organic layer was separated, dried over Na2SO4, and concentrated in vacuo. The residue was purified by column chromatography on silica gel (0-5% EtOAc in petroleum ether) affording the title compound (1.0 g). 1H NMR (400 MHz, DMSO-d6): δ 8.21 (s, 1H), 8.08 (s, 1H), 7.67 (dd, 1H), 7.61 (d, 1H), 5.85 (dd, 1H), 3.88-3.85 (m, 1H), 3.78-3.72 (m, 1H), 2.41-2.29 (m, 1H), 2.05-1.95 (m, 2H), 1.77-1.72 (m, 1H), 1.61-1.56 (m, 2H).

1. customThe organic layer was separated
2. dry with materialdried over Na2SO4
3. concentrationconcentrated in vacuo
4. customThe residue was purified by column chromatography on silica gel (0-5% EtOAc in petroleum ether)