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Pyridylidene ligand facilitates gold-catalyzed oxidative C-H arylation of heterocycles.

ABSTRACT: Triaryl-2-pyridylidene effectively facilitates the gold-catalyzed oxidative C-H arylation of heteroarenes with arylsilanes as a unique electron-donating ligand on gold. The employment of the 2-pyridylidene ligand, which is one of the strongest electron-donating N-heterocyclic carbenes, resulted in the rate acceleration of the C-H arylation reaction of heterocycles over conventional ligands such as triphenylphosphine and a classical N-heterocyclic carbene. In situ observation and isolation of the 2-pyridylidene-gold(III) species, as well as a DFT study, indicated unusual stability of gold(III) species stabilized by strong electron donation from the 2-pyridylidene ligand. Thus, the gold(I)-to-gold(III) oxidation process is thought to be facilitated by the highly electron-donating 2-pyridylidene ligand.

SUBMITTER: Hata K

PROVIDER: S-EPMC4734412 | biostudies-other | 2015

REPOSITORIES: biostudies-other

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Pyridylidene ligand facilitates gold-catalyzed oxidative C-H arylation of heterocycles.

Hata Kazuhiro K Ito Hideto H Segawa Yasutomo Y Itami Kenichiro K

Beilstein journal of organic chemistry 20151228

Triaryl-2-pyridylidene effectively facilitates the gold-catalyzed oxidative C-H arylation of heteroarenes with arylsilanes as a unique electron-donating ligand on gold. The employment of the 2-pyridylidene ligand, which is one of the strongest electron-donating N-heterocyclic carbenes, resulted in the rate acceleration of the C-H arylation reaction of heterocycles over conventional ligands such as triphenylphosphine and a classical N-heterocyclic carbene. In situ observation and isolation of the ...[more]

PMID: 26877796

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