Cesium carbonate → 6-Fluoro-1-[2-(tetrahydro-pyran-2-yloxy)-ethyl]-1H-indazole

Participants

Reaction Steps

A mixture of 6-fluoro-1H-indazole (2.0 g, 14.7 mmol), and 2-(2-bromo-ethoxy)-tetrahydro-pyran (3.38 g, 16.2 mmol) in DMF (25 mL) was treated with caesium carbonate (6.1 g, 18.7 mmol) and stirred at RT for 18 h. The solvent volume was reduced in vacuo, and the residue partitioned between EtOAc (100 mL) and water (100 mL). The aqueous layer was extracted into EtOAc (3×). The combined organic layers were washed with saturated aqueous sodium chloride solution, dried (MgSO4) and evaporated in vacuo. The residue was purified by FCC, using 0-50% cyclohexane in EtOAc, to afford the title product and a yellow oil. LCMS (Method 1): Rt 3.42 min, m/z 181 [MH+] (M-THP). 1H NMR (300 MHz; CDCl3) 1.52-1.56 (6 H, m), 3.39-3.49 (1 H, m), 3.57-3.68 (1 H, m), 3.89-3.91 (1 H, m), 4.19-4.21 (1 H, m), 4.56-4.57 (3 H, m), 6.88 (1 H, td, J 9.15 and 2.26), 7.30 (1 H, m), 7.62 (1 H, m), 8.04 (1 H, s).

Provenance & Evidence