Phosgene → (R)-3-(4-(isopropylsulfonyl)-3-(pyrrolidin-2-yl)phenyl)-1,1-dimethylurea hydrochloride

Participants

Reaction Conditions

Reaction Steps

To 40A (0.25 g, 0.68 mmol) in dichloromethane (5 mL) at 0° C. was added sodium bicarbonate (0.57 g, 6.8 mmol), then phosgene (0.71 mL, 1.36 mmol, 20% in tolouene). The reaction was stirred at 0° C. for 30 min. The crude mixture was filtered and washed with dichloromethane. To the filtrate was added triethylamine (0.27 mL, 2.04 mmol), then dimethylamine hydrochloride (0.083 g, 1.02 mmol) and the reaction was stirred for 2 h at rt. The solution was washed with water and brine and dried over sodium sulfate. The solvent was removed and the residue was redissolved in ethyl acetate (2 mL). HCl (4 mL, 4M in dioxane) was added and the reaction was stirred at rt for 4 h. The solvent was removed and dried under high vacuo. 1H NMR (400 MHz, Methanol-d4) δ ppm 1.23 (d, J=6.59 Hz, 3H) 1.31-1.40 (m, 3H) 2.14-2.27 (m, 1H) 2.29-2.43 (m, 2H) 2.44-2.60 (m, 1H) 3.02-3.11 (m, 6H) 3.37-3.53 (m, 3H) 5.42 (t, J=7.69 Hz, 1H) 7.64 (dd, J=8.79, 1.76 Hz, 1H) 7.91 (d, J=8.79 Hz, 1H) 8.08 (d, J=2.20 Hz, 1H).

Provenance & Evidence