Dimethylcarbamoyl Chloride → Dimethylcarbamoyloxy-phenyl-acetic acid

Participants

Reaction Steps

To hydroxyl-phenyl-acetic acid methyl ester (500 mg) in THF (10 mL) were added dimethylcarbamoyl chloride (304 μl), TEA (503 μl), and DMAP (37 mg). After stirring for overnight at room temperature, the mixture was taken up in ethyl acetate (150 mL). The organic phase was washed with 1 N HCl (1×100 mL) and saturated sodium bicarbonate (1×100 mL), and dried over sodium sulfate. After the solvent was removed, the resulting solid was dissolved in THF (6 mL). To the solution was added 2 M LiOH (3 mL). After stirring for 90 min. at room temperature, the reaction mixture was acidified with 2 N HCl (3.2 mL). The mixture was extracted with ethyl acetate (50 mL). The organic phase was dried over sodium sulfate. The solvent was removed under reduced pressure to provide dimethylcarbamoyloxy-phenyl-acetic acid (561 mg, 83%) as an off-white solid. [1-(2-{5-[6-(4-{2-[1-(2-Dimethylcarbamoyloxy-2-phenyl-acetyl)-pyrrolidin-2-yl]-3H-imidazol-4-yl)-naphthalen-2-yl]-1H-imidazol-2-yl}-pyrrolidine-1-carbonyl)-2-methyl-propyl]-carbamic acid methyl ester: To 2-{5-[4-(6-{2-[1-(2-Methoxycarbonylamino-3-methyl-butyryl)-pyrrolidin-2-yl]-3H-imidazol-4-yl]-naphthalen-2-yl}-1H-imidazol-2-yl]-pyrrolidine-1-carboxylic acid tert-butyl ester (40 mg) in methanol (0.5 mL) was added 4N HCl in dioxanes (0.5 mL). The mixture was stirred for 2 hours then concentrated to afford the HCl salt of the crude amine. To the crude amine in DMF (1 mL) was added DIEA (140). After all material dissolved, dimethylcarbamoyloxy-phenyl-acetic acid (12 mg) and (1-cyano-2-ethoxy-2-oxoethylidenaminooxy)dimethylamino-morpholino-carbenium hexafluorophosphate (COMU, 23 mg) were added. After stirring for 30 min. the reaction was purified by a preparative HPLC (10-60% MeCN—H2O; 0.1% formic acid modifier) to afford the title product (22 mg, 48%). 1H NMR (MeOH-d4, 400 MHz) δ: 8.22-8.05 (m, 2H), 7.92-7.69 (m, 9H), 7.56-7.44 (m, 6H), 6.08-5.92 (d, 1H), 5.27-5.20 (m, 2H), 4.28-4.24 (m, 1H), 4.13-4.00 (m, 2H), 3.90-3.68 (m, 2H), 3.66 (s, 3H), 3.45-3.38 (m, 2H), 2.92-2.90 (m, 6H), 2.47-1.96 (m, 10H), 1.05-0.91 (m, 6H); MS (ESI) m/z 837.3 [M+H]+.

Provenance & Evidence