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Gold(III) Alkyne Complexes: Bonding and Reaction Pathways.

ABSTRACT: The synthesis and characterization of hitherto hypothetical AuIII ?-alkyne complexes is reported. Bonding and stability depend strongly on the trans effect and steric factors. Bonding characteristics shed light on the reasons for the very different stabilities between the classical alkyne complexes of PtII and their drastically more reactive AuIII congeners. Lack of back-bonding facilitates alkyne slippage, which is energetically less costly for gold than for platinum and explains the propensity of gold to facilitate C-C bond formation. Cycloaddition followed by aryl migration and reductive deprotonation is presented as a new reaction sequence in gold chemistry.

SUBMITTER: Rocchigiani L

PROVIDER: S-EPMC5698712 | biostudies-literature | 2017 Oct

REPOSITORIES: biostudies-literature

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Gold(III) Alkyne Complexes: Bonding and Reaction Pathways.

Rocchigiani Luca L Fernandez-Cestau Julio J Agonigi Gabriele G Chambrier Isabelle I Budzelaar Peter H M PHM Bochmann Manfred M

Angewandte Chemie (International ed. in English) 20171002 44

The synthesis and characterization of hitherto hypothetical AuIII π-alkyne complexes is reported. Bonding and stability depend strongly on the trans effect and steric factors. Bonding characteristics shed light on the reasons for the very different stabilities between the classical alkyne complexes of PtII and their drastically more reactive AuIII congeners. Lack of back-bonding facilitates alkyne slippage, which is energetically less costly for gold than for pla ...[more]

PMID: 28892244

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