Water → (3S)-3-amino-3-phenylpropanoic acid

Reaction equation

[NH2:1][CH:2]([C:9]1[CH:14]=[CH:13][CH:12]=[CH:11][CH:10]=1)[CH2:3][C:4]([O:6]CC)=[O:5].O.[OH-].[Na+]>CC(C)=O>[NH2:1][C@H:2]([C:9]1[CH:14]=[CH:13][CH:12]=[CH:11][CH:10]=1)[CH2:3][C:4]([OH:6])=[O:5]

Participants

Procedure

9.2 mmol of the racemic compound ethyl rac-3-amino-3-phenylpropionate (1.79 g) are taken up in 50 ml of a solvent mixture composed of 25 ml of water and 25 ml of acetone as organic solvent. The solution is set to a pH of 8.2 by means of automatic pH adjustment through adding 1 M sodium hydroxide solution (obtained from Merck). On reaching a reaction temperature of 20° C., 200 mg of lipase PS (Pseudomonas cepacia; obtained through Amano Enzymes, Inc.) are added to start the reaction. After a reaction time of 3, 5 and 24 hours, the conversion rate of the (S)-3-amino-3-phenylpropionic acid formed is determined. A conversion of 1.8% after 3 hours, 2.0% after 5 hours and 5.5% after 24 hours is determined. The value of the enantioselectivity was not determined because of the unsatisfactory course of the reaction in view of the low conversion. The conversion is determined by means of HPLC.