Benzoic acid, 3-(chlorosulfonyl)-, methyl ester → 3-[(1-tert-Butoxycarbonyl-cyclobutylmethyl)-sulfamoyl]-benzoic acid methyl ester

Participants

Reaction Steps

A solution of 1-aminomethyl-cyclobutanecarboxylic acid tert-butyl ester (step 2) (1.47 g, 7.38 mmol) in DCM (40 ml) was treated with TEA (2.57 ml, 18.44 mmol) followed by methyl 3-(chlorosulfonyl)benzoate (1.91 g, 8.11 mmol) and DMAP (0.09 g, 0.74 mmol). The mixture was stirred at RT for 2 h and then partitioned between DCM and water. The aqueous portion was extracted with DCM and the combined organic extracts were washed with 0.1N HCl, brine, dried over MgSO4 and concentrated in vacuo. Purification of the resulting oil by chromatography on silica eluting with 0-40% EtOAc in iso-hexane afforded the title compound as a colourless oil; 1H NMR (400 MHz, CDCl3) δ 8.56 (1H, s), 8.27 (1H, d), 8.08 (1H, d), 7.64 (1H, t), 5.21 (1H, br t), 3.98 (3H, s), 3.20 (2H, d), 2.37 (2H, m), 1.96 (4H, m), 1.46 (9H, s).

Provenance & Evidence