Sodium Carbonate → phenyl (3-(tert-butyl)-1-(p-tolyl)-1H-pyrazol-5-yl)carbamate

Participants

Reaction Steps

A solution of 3-(tert-butyl)-1-(p-tolyl)-1H-pyrazol-5-amine (Intermediate A) (20 g, 87.0 mmol) in isopropyl acetate (240 mL) was added to a stirred solution of sodium carbonate (11.3 g, 106 mmol) in water (80 mL). After 10 min phenyl chloroformate (12.1 mL, 96 mmol) was added and the resulting mixture was stirred at ambient temperature overnight. The reaction mixture was diluted with water (160 mL), the layers were separated and the organics were washed with water (2×80 mL), brine (80 mL), dried (MgSO4) and concentrated in vacuo. The resulting yellow solid was suspended in 10% ether/iso-hexane (320 mL) and stirred until a uniform suspension was obtained. The solid was collected by filtration and washed with iso-hexane to yield the subtitle compound phenyl (3-(tert-butyl)-1-(p-tolyl)-1H-pyrazol-5-yl)carbamate as a white powder (27.3 g, 88%); Rt 2.65 min (Method 1); m/z 350 (M+H)+ (ES+); 1H NMR δ:1.29 (9H, s), 2.37 (3H, s), 6.35 (1H, s), 7.10-7.23 (3H, overlapping m), 7.33-7.46 (6H, overlapping m), 9.99 (1H, s).

Provenance & Evidence