Triethylamine → 4-(2-Chloro-6-methanesulfonylamino-phenyl)-piperazine-1-carboxylic acid tert-butyl ester

Participants

Reaction Conditions

Reaction Steps

4-(2-Amino-6-chloro-phenyl)-piperazine-1-carboxylic acid tert-butyl ester (163 mg, 0.53 mmol) in CH2Cl2 was treated with 62 L (0.80 mmol, 1.5 eq) of methanesulfonyl chloride and 148 L (1.06 mmol, 2 eq) of triethylamine and the reaction mixture stirred at 25° C. for 1 h. EtOAc (40 mL) and sat. NaHCO3 (20 mL) were added. The organic layer was separated and washed with H2O (20 mL), brine (20 mL), dried over Na2SO4, and concentrated. Column chromatography (silica, 0-5% acetone/CH2Cl2) provided 145 mg (70%) of 4-(2-chloro-6-methanesulfonylamino-phenyl)-piperazine-1-carboxylic acid tert-butyl ester. TLC (silica, 5% acetone/CH2Cl2): Rf=0.35. MS (electrospray): exact mass calculated for C16H24ClN3O4S, 389.12; m/z found, 388.1 (negative). 1H NMR (400 MHz, CDCl3): 7.41 (dd, J=8.2, 1.6 Hz, 1H), 7.11 (t, J=8.2 Hz, 1H), 6.99 (dd, J=8.2, 1.6 Hz, 1H), 4.25-3.91 (m, 2H), 3.66-3.52 (m, 2H), 3.01 (s, 3H), 3.01-2.84 (m, 2H), 2.70-2.56 (m, 2H), 2.55-2.43 (m, 2H), 1.44 (s, 9H).

Provenance & Evidence