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Deracemization by simultaneous bio-oxidative kinetic resolution and stereoinversion.

ABSTRACT: Deracemization, that is, the transformation of a racemate into a single product enantiomer with theoretically 100% conversion and 100% ee, is an appealing but also challenging option for asymmetric synthesis. Herein a novel chemo-enzymatic deracemization concept by a cascade is described: the pathway involves two enantioselective oxidation steps and one non-stereoselective reduction step, enabling stereoinversion and a simultaneous kinetic resolution. The concept was exemplified for the transformation of rac-benzylisoquinolines to optically pure (S)-berbines. The racemic substrates were transformed to optically pure products (ee>97%) with up to 98% conversion and up to 88% yield of isolated product.

SUBMITTER: Schrittwieser JH

PROVIDER: S-EPMC4499246 | biostudies-literature | 2014 Apr

REPOSITORIES: biostudies-literature

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Deracemization by simultaneous bio-oxidative kinetic resolution and stereoinversion.

Schrittwieser Joerg H JH Groenendaal Bas B Resch Verena V Ghislieri Diego D Wallner Silvia S Fischereder Eva-Maria EM Fuchs Elisabeth E Grischek Barbara B Sattler Johann H JH Macheroux Peter P Turner Nicholas J NJ Kroutil Wolfgang W

Angewandte Chemie (International ed. in English) 20140224 14

Deracemization, that is, the transformation of a racemate into a single product enantiomer with theoretically 100% conversion and 100% ee, is an appealing but also challenging option for asymmetric synthesis. Herein a novel chemo-enzymatic deracemization concept by a cascade is described: the pathway involves two enantioselective oxidation steps and one non-stereoselective reduction step, enabling stereoinversion and a simultaneous kinetic resolution. The concept was exemplified for the transfor ...[more]

PMID: 24615790

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