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C(sp(3))-F reductive elimination from alkylgold(iii) fluoride complexes.

ABSTRACT: Rare examples of C(sp(3))-F reductive elimination were observed from several cis-F(2)Au(R)(IPr) intermediates generated by oxidation of (IPr)AuR complexes with XeF(2). For R groups bearing ?-hydrogens, ?-hydride elimination was competitive with C(sp(3))-F reductive elimination. For strained cyclic R groups and most acyclic R groups lacking ?-hydrogens, carbocation-like rearrangements occurred prior to C(sp(3))-F reductive elimination. Kinetics of the decay of one cis-F(2)Au(R)(IPr) species, stereochemical analysis of reductive elimination with a chiral R group, and DFT analysis collectively suggest C(sp(3))-F reductive elimination proceeding through transient cationic [(IPr)Au(F)(R)](+) intermediates with significant ionization of the Au-alkyl bonds.

SUBMITTER: Mankad NP

PROVIDER: S-EPMC3474378 | biostudies-literature | 2012 Jan

REPOSITORIES: biostudies-literature

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C(sp(3))-F reductive elimination from alkylgold(iii) fluoride complexes.

Mankad Neal P NP Toste F Dean FD

Chemical science 20111013 1

Rare examples of C(sp(3))-F reductive elimination were observed from several cis-F(2)Au(R)(IPr) intermediates generated by oxidation of (IPr)AuR complexes with XeF(2). For R groups bearing β-hydrogens, β-hydride elimination was competitive with C(sp(3))-F reductive elimination. For strained cyclic R groups and most acyclic R groups lacking β-hydrogens, carbocation-like rearrangements occurred prior to C(sp(3))-F reductive elimination. Kinetics of the decay of one cis-F(2)Au(R)(IPr) species, ster ...[more]

PMID: 23087810

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