Pyridine → Phenyl 3-cyano-4-(ethylsulfonyl)phenylcarbamate

Participants

Reaction Steps

Phenylchloroformate (0.63 mL, 5 mmol) was added dropwise to a solution of 6B in methylene chloride (10 mL) and pyridine (0.60 mL, 7.1 mmol) at 0° C. After stirring for 1 h, the reaction mixture was partitioned between 1.0 M HCl (150 mL) and EtOAc (150 mL). The layers were separated and the organic phase was washed with saturated NaHCO3, brine, dried over Na2SO4 and concentrated. The crude product was purified by flash chromatography (0% to 100% EtOAc in hexanes) to yield 25A (1.34 g, 85%) as a white solid. 1H NMR (400 MHz, CD3OD) δ ppm 1.32 (t, J=7.45 Hz, 3 H) 3.36 (q, J=7.33 Hz, 2 H) 7.14-7.21 (m, J=7.58 Hz, 2 H) 7.26-7.31 (m, J=7.45, 7.45 Hz, 1 H) 7.37-7.45 (m, J=7.83, 7.83 Hz, 2 H) 7.66 (bs, 1 H) 7.83 (dd, J=8.72, 2.15 Hz, 1 H).

Provenance & Evidence