Sulfuric Acid → 3-Phenyllactic acid, (S)-

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

L-Phenylalanine (10.00 g, 60.5 mmol) was added to a dilution of 14.83 g (151.3 mmol) of concentrated sulfuric acid in 110 g of water and then, at an inside temperature of 20° C., a mixture of 10.45 g (151.5 mmol) of sodium nitrite and 20 g of water was added over 5 hours. After addition, the mixture was further stirred at 20° C. for 20 hours and, thereafter, the same work-up procedure as in Example 1 was followed. The combined extract (114.4 g) obtained contained 6.9 g of (2S)-2-hydroxy-3-phenylpropionic acid (yield 69%, optical purity 96.5% ee). The proton concentration (normality) in the reaction of this comparative example was 2.7 mol/kg, the amount of the protonic acid was 5.0 equivalents (relative to L-phenylalanine), and the reaction temperature was 20° C.

Herkunft & Nachweise