Allyl iodide → 6-Allyloxy-1H-indazole

Participants

Reaction Steps

To a solution of 1H-indazol-6-ol (20.0 g, 150 mmol) in acetone (450 mL) was added pulverized potassium carbonate (22.4 g, 162 mmol), cesium carbonate (2.00 g, 5.7 mmol), and allyl iodide (14.63 mL, 160 mmol) and the mixture was stirred for 18 h at ambient temperature. Additional potassium carbonate (5.00 g, 36 mmol) and allyl iodide (1.4 mL, 15 mmol) were added and the mixture was stirred for 2 h followed filtration. Water (200 mL) was added to the filtrate and the volume of the mixture was reduced by about half in vacuo and extracted with dichloromethane (2×100 mL). The combined extracts were dried (MgSO4) and evaporated to a residue which was purified by chromatography (silica, 20% to 50% EtOAc/hexane) to give a yellow solid (14.7 g, 56%): mp 110-112° C.; LC/MS (+APCI) m/z 175 (M+H). Unreacted starting material was recovered (4.71 g).

Provenance & Evidence