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?-?-Diauration as an alternative binding mode for digold intermediates in gold(i) catalysis.

ABSTRACT: While investigating the gold(i)-catalyzed intramolecular hydroarylation of allenes, the structure of a digoldvinyl intermediate was verified. Instead of the previously proposed geminally diaurated binding mode for the digold when L = PPh3, an alternative ?-?-diauration mode was observed with the bulkier ligand L = P(o-Tol)3. Reactivity studies indicate the ?-?-mode has a disproportionate effect on protonolysis reactivity.

SUBMITTER: Weber D

PROVIDER: S-EPMC3729438 | biostudies-literature | 2013

REPOSITORIES: biostudies-literature

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σ-π-Diauration as an alternative binding mode for digold intermediates in gold(i) catalysis.

Weber Dieter D Gagné Michel R MR

Chemical science 20130101 1

While investigating the gold(i)-catalyzed intramolecular hydroarylation of allenes, the structure of a digoldvinyl intermediate was verified. Instead of the previously proposed geminally diaurated binding mode for the digold when L = PPh3, an alternative σ-π-diauration mode was observed with the bulkier ligand L = P(o-Tol)3. Reactivity studies indicate the σ-π-mode has a disproportionate effect on protonolysis reactivity. ...[more]

PMID: 23914295

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