Dl-Phenylalanine → (-)-Mandelic acid

Participants

Reaction Conditions

Reaction Steps

To a vessel, were added 34.24 g of DL-phenylalanine, 47.31 g of D-mandelic acid and 174.2 g of an aqueous 50% acetic acid solution (the total weight of 255.75 g) while stirring. The resultant mixture was heated to form a solution. The solution was slowly cooled to 25° C. for 3 hours and then, was stirred at the same temperature for 2 hours. As a result, a complex of D-phenylalanine and D-mandelic acid was crystallized and the crystals were collected by filtration, were washed with 10 ml of water and were dried. A crude complex of D-phenylalanine and D-mandelic acid having [α]D20 of -56.50° (c=2, in H2O) and an optical purity of 91.0% was obtained in yield of 25.59 g.

Provenance & Evidence