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Iridium-catalyzed allylation of chiral ?-stereogenic alcohols: bypassing discrete formation of epimerizable aldehydes.

ABSTRACT: The cyclometalated ?-allyliridium 3,4-dinitro-C,O-benzoate complex modified by (R)- or (S)-Cl,MeO-BIPHEP promotes the transfer hydrogenative coupling of allyl acetate to ?-stereogenic alcohols with good to excellent levels of catalyst-directed diastereoselectivity to furnish homoallylic alcohols. Remote electronic effects of the C,O-benzoate of the catalyst play a critical role in suppressing epimerization of the transient ?-stereogenic aldehyde.

SUBMITTER: Schmitt DC

PROVIDER: S-EPMC3529126 | biostudies-literature | 2012 Dec

REPOSITORIES: biostudies-literature

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Iridium-catalyzed allylation of chiral β-stereogenic alcohols: bypassing discrete formation of epimerizable aldehydes.

Schmitt Daniel C DC Dechert-Schmitt Anne-Marie R AM Krische Michael J MJ

Organic letters 20121211 24

The cyclometalated π-allyliridium 3,4-dinitro-C,O-benzoate complex modified by (R)- or (S)-Cl,MeO-BIPHEP promotes the transfer hydrogenative coupling of allyl acetate to β-stereogenic alcohols with good to excellent levels of catalyst-directed diastereoselectivity to furnish homoallylic alcohols. Remote electronic effects of the C,O-benzoate of the catalyst play a critical role in suppressing epimerization of the transient α-stereogenic aldehyde. ...[more]

PMID: 23231774

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