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Isothiourea-Catalysed Acylative Kinetic Resolution of Aryl-Alkenyl (sp² vs. sp² ) Substituted Secondary Alcohols.

ABSTRACT: The non-enzymatic acylative kinetic resolution of challenging aryl-alkenyl (sp² vs. sp² ) substituted secondary alcohols is described, with effective enantiodiscrimination achieved using the isothiourea organocatalyst HyperBTM (1?mol?%) and isobutyric anhydride. The kinetic resolution of a wide range of aryl-alkenyl substituted alcohols has been evaluated, with either electron-rich or naphthyl aryl substituents in combination with an unsubstituted vinyl substituent providing the highest selectivity (S=2-1980). The use of this protocol for the gram-scale (2.5?g) kinetic resolution of a model aryl-vinyl (sp² vs. sp² ) substituted secondary alcohol is demonstrated, giving access to >1?g of each of the product enantiomers both in 99:1?e.r.

SUBMITTER: Musolino SF

PROVIDER: S-EPMC6680239 | biostudies-literature | 2016 Dec

REPOSITORIES: biostudies-literature

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Isothiourea-Catalysed Acylative Kinetic Resolution of Aryl-Alkenyl (sp2 vs. sp2 ) Substituted Secondary Alcohols.

Musolino Stefania F SF Ojo O Stephen OS Westwood Nicholas J NJ Taylor James E JE Smith Andrew D AD

Chemistry (Weinheim an der Bergstrasse, Germany) 20161130 52

The non-enzymatic acylative kinetic resolution of challenging aryl-alkenyl (sp2 vs. sp2 ) substituted secondary alcohols is described, with effective enantiodiscrimination achieved using the isothiourea organocatalyst HyperBTM (1 mol %) and isobutyric anhydride. The kinetic resolution of a wide range of aryl-alkenyl substituted alcohols has been evaluated, with either electron-rich or naphthyl aryl substituents in combination with an unsubstituted vinyl substituent providin ...[more]

PMID: 27775200

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