Abstract
We developed a one-pot sequential two-step deracemization approach to chiral alcohols using two mutants ofThermoanaerobacter pseudoethanolicussecondary alcohol dehydrogenase (TeSADH). This approach relies on consecutive non-stereospecific oxidation of alcohols and stereoselective reduction of their prochiral ketones using two mutants ofTeSADH with poor and good stereoselectivities, respectively. More specifically, W110GTeSADH enables a non-stereospecific oxidation of alcohol racemates to their corresponding prochiral ketones, followed by W110VTeSADH-catalyzed stereoselective reduction of the resultant ketone intermediates to enantiopure (S)-configured alcohols in up to > 99 % enantiomeric excess. A heat treatment after the oxidation step was required to avoid the interference of the marginally stereoselective W110GTeSADH in the reduction step; this heat treatment was eliminated by using sol-gel encapsulated W110GTeSADH in the oxidation step. Moreover, this bi-enzymatic approach was implemented in the stereoinversion of (R)-configured alcohols, and (S)-configured alcohols with up to > 99 % enantiomeric excess were obtained by this Mitsunobu-like stereoinversion reaction.