Cesium carbonate → tert-butyl (R)-1-(4-amino-2-(1-methyl-1H-pyrazol-5-yl)phenoxy)propan-2-ylcarbamate

Participants

Reaction Conditions

Reaction Steps

4-amino-2-(1-methyl-1H-pyrazol-5-yl)phenol (500 mg, 2643 μmol), (R)-tert-butyl 1-bromopropan-2-ylcarbamate (755 mg, 3171 μmol) and cesium carbonate (1205 mg, 3700 μmol) were weighed into a vial with anhydrous acetone (3.0 mL). The reaction was heated in a microwave at 100° C. for an hour. After this time, the crude LC/MS showed that the reaction was nearly complete. Thus, the solvent was evaporated and the resulting material was extracted (3 mL each of H2O and CH2Cl2). The aqueous layer was extracted again with CH2Cl2 (3 mL). The combined organic layer was dried over MgSO4, filtered, and concentrated. The product was purified by column chromatography (0, 20, 50, 70, 100% EtOAc/Hexanes) to yield tert-butyl(R)-1-(4-amino-2-(1-methyl-1H-pyrazol-5-yl)phenoxy)propan-2-ylcarbamate (487 mg, 1.41 mmol, 50.7%) as a light brown colored oil. LCMS m/z 347.1 (M+H); 1H NMR (400 MHz, MeOH-d4) δ ppm 0.92 (d, J=6.57 Hz, 3 H), 1.32 (s, 9 H), 3.60 (s, 3 H), 3.69-3.76 (m, 1 H), 3.79-3.94 (m, 2 H), 6.13 (d, J=1.77 Hz, 1 H), 6.57 (d, J=2.78 Hz, 1 H), 6.72 (dd, J=8.59, 2.78 Hz, 1 H), 6.83 (d, J=8.84 Hz, 1 H), 7.36 (d, J=2.02 Hz, 1 H).

Provenance & Evidence