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Driving Catalyst Reoxidation in Wacker Cyclizations with Acetal-Based Metal-Hydride Abstractors.

ABSTRACT: In traditional Wacker processes, Pd(II) becomes reduced to Pd(0) after C-O bond formation and ?-H elimination and must be reoxidized to the electrophilic Pd(II) state via a stoichiometric oxidant like benzoquinone, CuCl(2), or O(2). We report herein a Pt-catalyzed Wacker-type process that regenerates the electrophilic Pt(2+) state by H(-) abstraction from a [Pt]-H using an oxocarbenium ion generated from an acetal or ketal under acidic conditions.

SUBMITTER: Cochrane NA

PROVIDER: S-EPMC3092479 | biostudies-literature | 2011 May

REPOSITORIES: biostudies-literature

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Driving Catalyst Reoxidation in Wacker Cyclizations with Acetal-Based Metal-Hydride Abstractors.

Cochrane Nikki A NA Brookhart Maurice S MS Gagné Michel R MR

Organometallics 20110501 9

In traditional Wacker processes, Pd(II) becomes reduced to Pd(0) after C-O bond formation and β-H elimination and must be reoxidized to the electrophilic Pd(II) state via a stoichiometric oxidant like benzoquinone, CuCl(2), or O(2). We report herein a Pt-catalyzed Wacker-type process that regenerates the electrophilic Pt(2+) state by H(-) abstraction from a [Pt]-H using an oxocarbenium ion generated from an acetal or ketal under acidic conditions. ...[more]

PMID: 21572581

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