In a 100 ml RBF combine 4-(3-phenyl-indole-1-sulfonyl)-benzoic acid (2.5 g, 6.62 mmol) and THF (25 ml). Cool the solution in an ice water bath and add 4-methylmorpholine (0.73 ml, 7.29 mmol) follow by the portion wise addition of CDMT (1.16 g, 7.29 mmol). Stir the solution in an ice water bath for one hour. Add dropwise, a solution of 4-fluorobenzylamine (0.83 ml, 7.29 mmol) in THF (8 μl) to the reaction at 0° C. Stir the solution at 0° C. for five hours, and quench with 1N HCl (50 ml). Extract the reaction MTBE (2×50 ml), filter and wash with saturated aqueous sodium chloride (50 ml). Dry the organics over magnesium sulfate, filter and concentrate to give N-(4-fluoro-benzyl)-4-(3-phenyl-indole-1-sulfonyl)-benzamide (2.43 g) as a white solid. HPLC=95.5%, MS (ESI) m/z observed 485.1334 calculated 485.1335 (M+H).
