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A bonding model for gold(I) carbene complexes.

ABSTRACT: The last decade has witnessed dramatic growth in the number of reactions catalyzed by electrophilic gold complexes. While proposed mechanisms often invoke the intermediacy of gold-stabilized cationic species, the nature of bonding in these intermediates remains unclear. Herein, we propose that the carbon-gold bond in these intermediates is comprised of varying degrees of both sigma and pi-bonding; however, the overall bond order is generally less than or equal to unity. The bonding in a given gold-stabilized intermediate, and the position of this intermediate on a continuum ranging from gold-stabilized singlet carbene to gold-coordinated carbocation, is dictated by the carbene substituents and the ancillary ligand. Experiments show that the correlation between bonding and reactivity is reflected in the yield of gold-catalyzed cyclopropanation reactions.

SUBMITTER: Benitez D

PROVIDER: S-EPMC2748951 | biostudies-literature | 2009 Sep

REPOSITORIES: biostudies-literature

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A bonding model for gold(I) carbene complexes.

Benitez Diego D Shapiro Nathan D ND Tkatchouk Ekaterina E Wang Yiming Y Goddard William A WA Toste F Dean FD

Nature chemistry 20090901 6

The last decade has witnessed dramatic growth in the number of reactions catalyzed by electrophilic gold complexes. While proposed mechanisms often invoke the intermediacy of gold-stabilized cationic species, the nature of bonding in these intermediates remains unclear. Herein, we propose that the carbon-gold bond in these intermediates is comprised of varying degrees of both sigma and pi-bonding; however, the overall bond order is generally less than or equal to unity. The bonding in a given go ...[more]

PMID: 20161015

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