Reaktion #11017

Reaktionsgleichung

sodium nitrite

L-Phenylalanine

sulfuric acid

→

(2S)-2-hydroxy-3-phenylpropionic acid

Ausbeute 64.0%

Lösungsmittel

water

water

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONwas added over 5 hours
2. 2
   workup.ADDITIONAfter addition
3. 3
   ExtraktionThe combined extract (116.5 g)
4. 4
   Sonstigeobtained

Vorschrift

L-Phenylalanine (10.00 g, 60.5 mmol) was added to a dilution of 8.88 g (90.5 mmol) of concentrated sulfuric acid in 55 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 (116.5 g) obtained contained 6.4 g of (2S)-2-hydroxy-3-phenylpropionic acid (yield 64%, optical purity 96.6% ee). The proton concentration (normality) in the reaction of this example was 3.3 mol/kg, the amount of the protonic acid was 3.0 equivalents (relative to L-phenylalanine), and the reaction temperature was 20° C.

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