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Dynamic kinetic resolution of transient hemiketals: a strategy for the desymmetrisation of prochiral oxetanols.

ABSTRACT: Identification of an electron poor trifluoroacetophenone allows the formation of uniquely stable hemiketals from prochiral oxetanols. When exposed to a cobalt(ii) catalyst, efficient ring-opening to densely functionalized dioxolanes is observed. Mechanistic studies suggest an unprecedented redox process between the cobalt(ii) catalyst and the hemiketal that initiates the oxetane-opening. Based on this observation, a dynamic kinetic resolution of the transient hemiketals is explored that uses a Katsuki-type ligand for stereoinduction (up to 99 : 1 dr and 96 : 4 er) and allows a variety of 1,3-dioxolanes to be accessed (20 examples up to 98% yield).

SUBMITTER: Sandvoß A

PROVIDER: S-EPMC9159106 | biostudies-literature | 2022 Jun

REPOSITORIES: biostudies-literature

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Dynamic kinetic resolution of transient hemiketals: a strategy for the desymmetrisation of prochiral oxetanols.

Sandvoß Alexander A Maag Henning H Daniliuc Constantin G CG Schollmeyer Dieter D Wahl Johannes M JM

Chemical science 20220504 21

Identification of an electron poor trifluoroacetophenone allows the formation of uniquely stable hemiketals from prochiral oxetanols. When exposed to a cobalt(ii) catalyst, efficient ring-opening to densely functionalized dioxolanes is observed. Mechanistic studies suggest an unprecedented redox process between the cobalt(ii) catalyst and the hemiketal that initiates the oxetane-opening. Based on this observation, a dynamic kinetic resolution of the transient hemiketals is explored that uses a K ...[more]

PMID: 35733901

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