An Efficient Method for Racemization of (S)‐3‐Carbamoylmethyl‐5‐methylhexanoic Acid

(S)-3-Carbamoylmethyl-5-methylhexanoic acid was heated in xylene and converted into 4-isobutyl-piperidine- 2,6-dione, which was hydrolyzed in aqueous solution of sodium hydroxide to afford the racemate. Our process is much advantageous over the traditional one, with not only less time (ca. 20 h) but also higher yield (76.4%).

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