Involved in the degradation of unsaturated organohalogen compounds. Catalyzes the NADPH-dependent reduction of the carbon-carbon double bond of 2-chloroacrylate to produce (S)-2-chloropropionate, which is probably further metabolized to (R)-lactate by (S)-2-haloacid dehalogenase. Can also use 2-bromoacrylate as substrate. Does not act on acrylate, methacrylate, 1,4-benzoquinone and 1,4-naphthoquinone. (S)-2-chloropropanoate + NADP(+) = 2-chloroacrylate + H(+) + NADPH (S)-2-chloropropionate is used in a large quantity as a synthetic precursor for the industrial production of aryloxyphenoxypropionic acid herbicides. Belongs to the zinc-containing alcohol dehydrogenase family.