Water → N-(2-benzoylphenyl)tyrosine methyl ester

Participants

Reaction Conditions

Reaction Steps

A stirred mixture of 92 g (0.45 mol) 2-benzoyl-cyclohexanone, (Denny, W. A. et. al. J. Med. Chem. 1978, 21(5), 430-7) 78 g (0.40 mol) L-Tyrosine methyl ester, 17.0 g Palladium on activated carbon (10%) was refluxed for 2 h in 1 L anisole while the resulting water was removed by a Dean-Stark apparatus. The mixture was cooled to 80° C. and the Pd/C was filtered, and washed with 50 mL anisole three times. The mixture was cooled to 40° C., 1 L hexane was added and kept at −20° C. for 48 h. The solid was filtered, washed with 200 mL hexane five times to yield 89.0 g crude (S)-2-(2-Benzoyl-phenylamino)-3-(4-hydroxy-phenyl)-propionic acid methyl ester. This solid was mixed with 220 mL of MeOH, and the slurry was refluxed for 30 min. The mixture was cooled to 0° C., the product was filtered and washed with 50 mL cold (−20° C.) MeOH twice, then dried under reduced pressure to yield 67.4 g the of the title compound. mp 185-6° C.; low resolution MS (ESP+) m/e 376 (MH+).

Provenance & Evidence