2-Chloropropionic acid dehalogenase

The only chiral intermediate is the chloroacid 116 which Zeneca manufacture as a racemic compound. They use the enzyme chloropropionic acid dehalogenase to destroy the unwanted isomer by conversion to lactic acid. It is easy to separate these two compounds as they are not even isomers. 

Another chiral small molecule, (S)-2-chloropropionic acid (S-CPA), is a key intermediate in the synthesis of the 2-phe-noxypropionic acid class of herbicides, including Fusilade (Avecia) and Mecoprop (BASF). Kinetic resolution of racemic CPA is performed with a whole cell biocatalyst expressing a dehalogenase enzyme selective for the (R)-enantiomer and producing (S)-lactic acid, itself a useful byproduct. The (S)-chloropropionic acid is extracted with a... 

S)-2-chloropropionic acid by enantioselective dehalogenation racemate (R)-specific dehalogenase... 

C-Cl hydrolysis for 2-chloropropionic acid with whole cells of Pseudomonas putida (dehalogenase) 2000 t/y Zeneca Life Science Molecules [3]... 

Enzymes are often used in kinetic resolutions, when one isomer reacts much faster than the other.25 This can be done on an industrial scale. Zeneca uses a dehalogenase on racemic 2-chloropropionic acid to obtain about 2000 ton/yr of the L-isomer for use in making a herbicide.26 Enzymatic resolutions may involve ring opening of epoxides,27 formation or hydrolysis of esters and amides, reduction of carbonyl compounds, and so on. Lipases are often used for this purpose.28 A typical example is reaction 10.16.29... 

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