Benzoyl chloride → Benzenepropanoic acid, beta-(benzoylamino)-alpha-hydroxy-, methyl ester, (alphaR,betaS)-

Participants

Reaction Conditions

Reaction Steps

A mixture of 1.51 g (6.83 mmol) of (+)-[methyl (2R,3S)-3-azido-2-hydroxy-3-phenylpropionate ], 1.93 g (13.7 mmol) of benzoyl chloride, 2.07 g (20.4 mmol) of triethylamine and 30.2 mg (0.25 mmol) of 4-dimethylaminopyridine in 27 cm3 of ethyl acetate is stirred under an argon atmosphere at 20° C. for 4 hours, and 1.4 cm3 of methanol are then added. The mixture is stirred for a further 3 hours, 152 mg of palladium on charcoal containing 10% (w/w) of palladium are then added and the mixture is placed under a hydrogen atmosphere. It is stirred for 68 hours. The hydrogen is replaced by argon, the reaction mixture is diluted in 100 cm3 of methylene chloride and the palladium on charcoal is removed by filtration under vacuum through Celite. The solids are washed 3 times with 20 to 30 cm3 of methylene chloride and the solvents are then removed under vacuum. A crude product is obtained, which is purified by chromatography on silica gel, eluting with an ether/dichloromethane mixture (5:95 by volume). 1.88 g of (-)-(2R,3S)-N-benzoyl-3-phenylisoserine methyl ester are thereby obtained, the characteristics of which are as follows:

Provenance & Evidence