title: 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.
authors.affiliation: Graduate School of Science, Nagoya University, Chikusa, Nagoya 464-8602, Japan.
authors.forename: Kazuhiro
authors.initials: K
authors.lastname: Hata
authors.affiliation: Graduate School of Science, Nagoya University, Chikusa, Nagoya 464-8602, Japan.
authors.forename: Hideto
authors.initials: H
authors.lastname: Ito
authors.affiliation: Graduate School of Science, Nagoya University, Chikusa, Nagoya 464-8602, Japan; JST, ERATO, Itami Molecular Nanocarbon Project, Nagoya University, Chikusa, Nagoya 464-8602, Japan.
authors.forename: Yasutomo
authors.initials: Y
authors.lastname: Segawa
authors.affiliation: Graduate School of Science, Nagoya University, Chikusa, Nagoya 464-8602, Japan; JST, ERATO, Itami Molecular Nanocarbon Project, Nagoya University, Chikusa, Nagoya 464-8602, Japan; Institute of Transformative Bio-Molecules (WPI-ITbM), Nagoya University, Chikusa, Nagoya 464-8602, Japan.
authors.forename: Kenichiro
authors.initials: K
authors.lastname: Itami
keywords: C–H arylation; carbene ligand; gold catalysis