[C:1]([OH:4])(=[O:3])[CH3:2].[C:5]([NH:8][C:9](=[CH:13][C:14]1[CH:19]=[CH:18][C:17]([OH:20])=[C:16]([O:21][CH3:22])[CH:15]=1)[C:10]([OH:12])=[O:11])(=[O:7])[CH3:6].[OH-].[Na+].[H][H].CP(C1C=CC=CC=1)CC1C(OC)=CC=CC=1>C1C=CC=CC=1.[Rh].O.CO>[C:1]([OH:4])(=[O:3])[CH3:2].[C:5]([NH:8][C@H:9]([C:10]([OH:12])=[O:11])[CH2:13][C:14]1[CH:19]=[CH:18][C:17]([OH:20])=[C:16]([O:21][CH3:22])[CH:15]=1)(=[O:7])[CH3:6]A one liter autoclave was charged with 100 grams (0.341 mole) of α-acetamido-4-hydroxy-3-methoxy-cinnamic acid acetate, 254 milliliters of methanol, 170 milliliters of water and 13.7 (0.341 mole) sodium hydroxide. The slurry obtained was brought to about 25° C. and 40 psig. hydrogen pressure and a catalyst solution in 6 milliliters of benzene that was made from 0.025 gram (0.115 milli-equivalents) of rhodium 1,5-hexadiene chloride [Rh-(1,5-hexadiene)Cl]2 (J. Am. Chem. Soc. 86, 217 (1964)), and 0.058 gram (0.250 milli-equivalents) (+) methylphenyl-o-anisylphosphine (while preventing intrusion of air) is added. (The catalyst charge is equivalent to 0.0118 gram rhodium metal.) Hydrogen is absorbed immediately and is complete in 8 hours, giving the compound, N-acetyl-3-(4-hydroxy-3-methoxyphenyl)-alanine acetate, with 80 percent of such compound being present as the L enantiomorph and 20 percent being present as a D enantiomorph.
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