Benzaldehyde → HCID 11437078, compound

Participants

Reaction Conditions

Reaction Steps

L-phenylalanine methyl ester hydrochloride (120.00 g), benzaldehyde (56.5 ml), anhydrous sodium sulfate (158.07 g) and triethylamine (77.5 ml) were added to tert-butylmethyl ether (480 ml), and the mixture was stirred overnight at 5° C. The solid was filtered off from the reaction solution, and the solvent was distilled off under reduced pressure. Then, n-hexane was added, and the solvent was distilled off again under reduced pressure. To the concentrate was added n-hexane, and the crystallization was conducted by cooling with ice to obtain desired N-(phenylmethylene)-L-phenylalanine methyl ester (126.01 g) in a yield of 85.0%. Further, the mother liquor was concentrated under reduced pressure, and the concentrate was crystallized by cooling with ice to obtain N-(phenylmethylene)-L-phenylalanine methyl ester (13.86 g) in a yield of 9%. Thus, the crystals of N-(phenylmethylene)-L-phenylalanine methyl ester were obtained in a total yield of 94%. A part of the resulting crystals were converted into a phenylalanine methyl ester. It was analyzed by HPLC using an optically active column, and identified to have the optical purity of >99.5% e.e.

Provenance & Evidence