Cesium carbonate → 1-(3-methoxy-4-nitro-1H-pyrazol-1-yl)propan-2-ol

Participants

Reaction Conditions

Reaction Steps

To a suspension of 3-methoxy-4-nitro-1H-pyrazole (2.00 g, 14.0 mmol, 1.00 eq) and cesium carbonate (13.7 g, 41.9 mmol, 3.0 eq) was added 1-bromo-2-propanol (2.70 mL, 22.4 mmol, 1.60 eq, 70% purity) and the reaction mixture was heated at 60° C. After 3.5 hr, an additional portion of 1-bromo-2-propanol (2.70 mL, 22.4 mmol, 1.60 eq, 70% purity) was added. After a further 12 hr, the reaction mixture was cooled to ambient temperature and diluted with water (100 mL) and EtOAc (50 mL). The layers were separated and the aqueous phase was extracted with EtOAc (4×50 mL). The combined organics were washed with water (50 mL) and brine (50 mL), dried (Na2SO4), concentrated, and purified via flash chromatography on silica gel eluting with a gradient of 0-50% EtOAc in heptane to give the title compound (945 mg, 34% yield) as a white solid. 1H NMR (400 MHz, CDCl3) δ ppm 8.09 (s, 1H), 4.32-4.22 (m, 1H), 4.06 (s, 3H), 4.05 (dd, J=5.0, 13.0 Hz, 1H), 3.87 (dd, J=8.0, 13.0 Hz, 1H), 2.60 (br. s., 1H), 1.29 (d, J=6.4 Hz, 3H). m/z (APCI+) for C7H12N3O4 201.9 (M+H)+.

Provenance & Evidence