Ammonia → HCID 53902585, compound

Participants

Reaction Steps

N,N-dibenzyl-L-phenylalanine hydrochloride (7.64 g, 20.0 mmol) was added to 50 ml of chloroform, and 20.0 ml of 10% aqueous ammonia were added dropwise to the suspension for neutralization. The organic layer was separated, washed with 20 ml of water, then dried over magnesium sulfate, and filtered. The filtrate was concentrated, the resulting residue was dissolved in 50 ml of chloroform, and 2.89 g (20.4 mmol) of p-nitrophenol and 4.13 g (20.0 mmol) of N,N′-dicyclohexylcarbodiimide were added to the solution in this order while being cooled with ice. The mixture was reacted overnight. To the reaction solution were added 30 ml of ethyl acetate, and the N,N′-dicyclohexylurea which precipitated was removed by filtration. The filtrate was washed with a 10% potassium carbonate aqueous solution. The organic layer was separated, and concentrated. The resulting residue was redissolved in 30 ml of ethyl acetate, and the insoluble materials which precipitated were removed by filtration. The filtrate was concentrated, and the resulting crude product was purified through silica-gel column chromatography to obtain 7.77 g (16.65 mmol) of the above-mentioned compound (Ib).

Provenance & Evidence