Synthesis of NHC-Iridium(III) Complexes Based on<i>N</i>-Iminoimidazolium Ylides and Their Use for the Amine Alkylation by Borrowing Hydrogen Catalysis
作者:Vincent Guérin、Claude Y. Legault
DOI:10.1021/acs.organomet.0c00726
日期:2021.2.8
ylides, were used to synthesize NHC-iridium(III) complexes. Their catalytic activities were evaluated in the amine alkylation of anilines using borrowing hydrogen catalysis. The high-yielding synthesis of a small library of complexes allowed a rapid screening of the ideal steric bulk of the NHC unit and basicity of the anionic tether for the investigated model reaction. A bulky aromatic N group on
<i>N</i>-Acyliminoimidazolium Ylides as Precursors to Anionic <i>N</i>-Heterocyclic Carbene Ligands: Control of Topology and Reactivity
作者:Hannah Guernon、Claude Y. Legault
DOI:10.1021/om400078f
日期:2013.3.25
A family of N-heterocyclic carbene ligands based on N-acyl iminoimidazolium ylides has been developed and investigated. The ylides are stable and are easily obtained in two steps. Following deprotonation, they form bidentate anionic NHC ligands. The synthesis of silver(I) complexes was explored. Different complex structures have been obtained, depending on the steric and electronic properties of the starting ylide proligands. Dimeric structures were usually obtained, but trimeric structures were observed under certain conditions. DFT calculations were used to explain these results. The electronic properties of the complexes can be modified by the choice of the electron-withdrawing group attached to the anionic tether. The silver complexes are proficient ligand transfer agents. The first example of a proligand/ligand exchange was demonstrated. The catalytic activity of the silver complexes was evaluated in a model (3 + 2) heterocycloaddition of an imino ester with an activated alkene.
Structure and reactivity of a new anionic N-heterocyclic carbene silver(i) complex
作者:Claude Y. Legault、Christopher Kendall、André B. Charette
DOI:10.1039/b506232b
日期:——
The efficient synthesis of aN-benzoyliminoimidazolium ylide provides access to a new type of N-hetereocyclic anionic carbene, from which air stable Ag(I) and Cu(II) complexes and a catalytically active Rh(I) complex were formed.