An Electron‐Deficient Cp<sup>E</sup> Iridium(III) Catalyst: Synthesis, Characterization, and Application to Ether‐Directed C−H Amidation
Eiki Tomita, M. Kojima, Yuki Nagashima, Ken Tanaka, Haruki Sugiyama, Yasutomo Segawa, Atsushi Furukawa, Katsumi Maenaka, Satoshi Maeda, Tatsuhiko Yoshino, Shigeki Matsunaga
Abstract
Abstract The synthesis, characterization, and catalytic performance of an iridium(III) catalyst with an electron‐deficient cyclopentadienyl ligand ([Cp E IrI 2 ] 2 ) are reported. The [Cp E IrI 2 ] 2 catalyst was synthesized by complexation of a precursor of the Cp E ligand with [Ir(cod)OAc] 2 , followed by oxidation, desilylation, and removal of the COD ligand. The electron‐deficient [Cp E IrI 2 ] 2 catalyst enabled C−H amidation reactions assisted by a weakly coordinating ether directing group. Experimental mechanistic studies and DFT calculations suggested that the high catalytic performance of [Cp E IrI 2 ] 2 is due to its electron‐deficient nature, which accelerates both C−H activation and Ir V ‐nitrenoid formation.