Related Experiment Video
Updated: Sep 27, 2025

Retropinacol/Cross-pinacol Coupling Reactions - A Catalytic Access to 1,2-Unsymmetrical Diols
Published on: April 4, 2014
Deracemization of 1-phenylethanols in a one-pot process combining Mn-driven oxidation with enzymatic reduction
Hirofumi Sato1, Rei Yamada2, Yomi Watanabe1
1Osaka Research Institute of Industrial Science and Technology 1-6-50 Morinomiya, Joto-ku Osaka 536-8553 Japan hsato@omtri.or.jp.
Abstract:
Racemic 1-phenylethanols were converted into enantiopure (R)-1-phenylethanols via a chemoenzymatic process in which manganese oxide driven oxidation was coupled with enzymatic biotransformation by compartmentalization of the reactions, although the two reactions conducted under mixed conditions are not compatible due to enzyme deactivation by Mn ions. Achiral 1-phenylethanol is oxidized to produce acetophenone in the interior chamber of a polydimethylsiloxane thimble. The acetophenone passes through the membrane into the exterior chamber where enantioselective biotransformation takes place to produce (R)-1-phenylethanol with an enantioselectivity of >99% ee and with 96% yield. The developed sequential reaction could be applied to the deracemization of a wide range of methyl- and chloro-substituted 1-phenylethanols (up to 93%, >99% ee). In addition, this method was applied to the selective hydroxylation of ethylbenzene to afford chiral 1-phenylethanol.
Related Concept Videos
Oxymercuration-Reduction of Alkenes
Oxidation of Alcohols
The process of oxidation in a chemical reaction is observed in any of the three forms:
Oxidation of Alkenes: Anti Dihydroxylation with Peroxy Acids
α-Hydroxy Ketones via Reductive Coupling of Esters: Acyloin Condensation Overview
Alkenes via Reductive Coupling of Aldehydes or Ketones: McMurry Reaction
Alcohols from Carbonyl Compounds: Reduction
Catalytic hydrogenation is similar to the reduction of an alkene or alkyne by adding H2 across the pi bond in the presence of transition metal catalysts like Raney Ni, Pd–C, Pt, or Ru. Aldehydes and ketones can be reduced by this method, often under mild to moderate heat (25–100°C) and...

