1,1'-Carbonyldiimidazole → HCID 131728696, compound

Participants

Reaction Steps

(Step 3) To (2R)-3-[(tert-butoxycarbonyl)amino]-2-(5-chloro-2-methoxybenzyl)propanoic acid (15 g) in tetrahydrofuran (75 ml) solution, 1,1′-carbonyldiimidazole (7.8 g) was added under ice cooling and the mixture was stirred at room temperature for 1 hour. The reaction solution was cooled to 0° C., 28% ammonia water (15 ml) was added, and the mixture was stirred at room temperature for 30 minutes. To the reaction solution, distilled water, ethyl acetate, and tetrahydrofuran were added, the aqueous layer and the organic layer were separated, and the aqueous layer was extracted with ethyl acetate. The combined organic layer was successively washed with saturated potassium hydrogensulfate aqueous solution and saturated saline, dried over with anhydrous sodium sulfate, and concentrated until a small amount of ethyl acetate remained. Hexane was added to the concentrated solution, and the precipitated solid was collected by filtration to obtain the title compound (13.5 g).

Provenance & Evidence