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Enantioselective Formation of All-Carbon Quaternary Centers via C-H Functionalization of Methanol: Iridium-Catalyzed Diene Hydrohydroxymethylation.

ABSTRACT: The first catalytic enantioselective C-C couplings of methanol (>30 × 106 tons/year) are reported. Insertion of 2-substituted dienes into the methanol C-H bond occurs in a regioselective manner to form all-carbon quaternary centers with excellent levels of enantioselectivity using an iridium-PhanePhos catalyst. Mechanistic studies corroborate a Curtin-Hammett scenario in which methanol dehydrogenation triggers rapid, reversible diene hydrometalation en route to regioisomeric allyliridium-formaldehyde pairs, yet single constitutional isomers are formed.

SUBMITTER: Nguyen KD

PROVIDER: S-EPMC5094804 | biostudies-literature | 2016 Nov

REPOSITORIES: biostudies-literature

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Enantioselective Formation of All-Carbon Quaternary Centers via C-H Functionalization of Methanol: Iridium-Catalyzed Diene Hydrohydroxymethylation.

Nguyen Khoa D KD Herkommer Daniel D Krische Michael J MJ

Journal of the American Chemical Society 20161020 43

The first catalytic enantioselective C-C couplings of methanol (>30 × 10<sup>6</sup> tons/year) are reported. Insertion of 2-substituted dienes into the methanol C-H bond occurs in a regioselective manner to form all-carbon quaternary centers with excellent levels of enantioselectivity using an iridium-PhanePhos catalyst. Mechanistic studies corroborate a Curtin-Hammett scenario in which methanol dehydrogenation triggers rapid, reversible diene hydrometalation en route to regioisomeric allylirid ...[more]

PMID: 27762549

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