Lithium iodide → 3-(2-tert-Butoxycarbonyl-ethylsulfamoyl)-benzoic acid

Participants

Reaction Steps

A solution of 3-(2-tert-Butoxycarbonyl-ethylsulfamoyl)-benzoic acid methyl ester (step 1) (5.0 g, 14.56 mmol) and lithium iodide (2.53 g, 18.93 mmol) in pyridine (60 ml) was heated at reflux for 16 h. The reaction mixture was concentrated in vacuo, diluted with DCM (60 ml) and poured into 1.5N HCl (60 ml). The aqueous phase was separated and extracted with DCM (6×60 ml). The combined organic extracts were dried (MgSO4) and concentrated in vacuo. The crude residue was purified using an Isolute® PE-AX 10 g cartridge (anion exchange column), eluting with MeOH (200 ml) and then a 1:1 mixture of MeOH/AcOH (200 ml) to afford the title compound as white crystals; 1H NMR (400 MHz, CDCl3) δ 8.63 (1H, s), 8.32(1H, d), 8.14(1H, d), 7.68 (1H, t), 5.63 (1H, t), 3.22 (2H, m), 2.51(2H, t), 1.43 (9H, s).

Provenance & Evidence