Acetonitrile → (R)-2-benzyloxycarbonyl-amino-3-(1-methylcyclopentyl)propionic acid methyl ester
Reaction equation
[CH3:1][O:2][C:3](=[O:23])[CH:4]([NH:12]C(OCC1C=CC=CC=1)=O)[CH2:5][C:6]1([CH3:11])[CH2:10][CH2:9][CH2:8][CH2:7]1.[C:24](#N)[CH3:25]>C([O-])(O)=O.[Na+]>[CH3:1][O:2][C:3](=[O:23])[C@@:4]([NH2:12])([C:3]([O:2][CH2:1][C:25]1[CH:24]=[CH:7][CH:6]=[CH:5][CH:4]=1)=[O:23])[CH2:5][C:6]1([CH3:11])[CH2:7][CH2:8][CH2:9][CH2:10]1Participants
4
Procedure
2-Benzyloxycarbonylamino-3-(1-methylcyclopentyl)-propionic acid methyl ester (7.6 g, 23.8 mmol) was dissolved in a mixture of acetonitrile (82 mL) and 0.2 M aqueous NaHCO3 (158 mL) and Alcalase 2.4 L (1.1 mL) was added and the reaction mixture was stirred vigorously for 8 h. The reaction mixture was then evaporated at 30° C. to remove acetonitrile, and the aqueous residue was washed with ether. The ethereal layer was concentrated to yield (R)-2-benzyloxycarbonyl-amino-3-(1-methylcyclopentyl)propionic acid methyl ester (1.9 g). The aqueous phase was filtered with Celite®, the pH was adjusted to 3 with 6N HCl, and the solution was extracted with ethylacetate. The ethyl acetate layer was dried and evaporated to yield 2(8)-benzyloxycarbonylamino-3-(1-methylcyclopentyl)-propionic acid (1.4 g).