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Rapid C-H bond activation by a monocopper(III)-hydroxide complex.

ABSTRACT: One-electron oxidation of the tetragonal Cu(II) complex [Bu(4)N][LCuOH] at -80 °C generated the reactive intermediate LCuOH, which was shown to be a Cu(III) complex on the basis of spectroscopy and theory (L = N,N'-bis(2,6-diisopropylphenyl)-2,6-pyridinedicarboxamide). The complex LCuOH reacts with dihydroanthracene to yield anthracene and the Cu(II) complex LCu(OH(2)). Kinetic studies showed that the reaction occurs via H-atom abstraction via a second-order rate law at high rates (cf. k = 1.1(1) M(-1) s(-1) at -80 °C, ?H(‡) = 5.4(2) kcal mol(-1), ?S(‡) = -30(2) eu) and with very large kinetic isotope effects (cf. k(H)/k(D) = 44 at -70 °C). The findings suggest that a Cu(III)-OH moiety is a viable reactant in oxidation catalysis.

SUBMITTER: Donoghue PJ

PROVIDER: S-EPMC3213683 | biostudies-literature | 2011 Nov

REPOSITORIES: biostudies-literature

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Rapid C-H bond activation by a monocopper(III)-hydroxide complex.

Donoghue Patrick J PJ Tehranchi Jacqui J Cramer Christopher J CJ Sarangi Ritimukta R Solomon Edward I EI Tolman William B WB

Journal of the American Chemical Society 20111017 44

One-electron oxidation of the tetragonal Cu(II) complex [Bu(4)N][LCuOH] at -80 °C generated the reactive intermediate LCuOH, which was shown to be a Cu(III) complex on the basis of spectroscopy and theory (L = N,N'-bis(2,6-diisopropylphenyl)-2,6-pyridinedicarboxamide). The complex LCuOH reacts with dihydroanthracene to yield anthracene and the Cu(II) complex LCu(OH(2)). Kinetic studies showed that the reaction occurs via H-atom abstraction via a second-order rate law at high rates (cf. k = 1.1(1 ...[more]

PMID: 22004091

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