1,1'-Carbonyldiimidazole → HCID 57978296, compound

Participants

Reaction Steps

A mixture of 4-{2-[(tert-butoxycarbonyl)amino]ethyl}benzoic acid (22.2 g, 83.6 mmol) (EP0836839, p60) carbonyldiimidazole (21.36 g, 131.7 mmol), and N,N-diisopropylethylamine (20 mL, 115.1 mmol) in dichloromethane (600 mL) was stirred at room temperature for 2 hours. nButylamine (10 mL, 101.18 mmol) was then added and the mixture was stirred for a further 18 hours at room temperature. The reaction mixture was concentrated in vacuo and the residue was dissolved in ethyl acetate and washed with 10% citric acid (2×50 mL), saturated sodium hydrogen carbonate solution (200 mL), water (200 mL) and brine (200 mL). The organic solution was dried over sodium sulfate and concentrated in vacuo to give a cream powder. The powder was purified by column chromatography on silica gel, eluting with dichloromethane:methanol, 99:1, to afford the title compound (17.5 g, 65%). LRMS Cl m/z 383.3 [M+NH4]+, m.p.=118° C.

Provenance & Evidence