of tetranuclear Rh(I) and Ir(I) complexes. The tetra-NHC ligand displays axial chirality upon coordination to the MCl(cod) (M = Rh and Ir) fragments, giving rise to right- and left-handed helix conformations. The catalytic activity of the resulting complexes was studied in two relevant reactions that lead to the formation of five- and six-membered oxygen-containing heterocycles, namely, the cyclization
Cyclic (Amino)(aryl)carbenes (CAArCs) as Strong σ‐Donating and π‐Accepting Ligands for Transition Metals
作者:Bin Rao、Huarong Tang、Xiaoming Zeng、Liu Leo Liu、Mohand Melaimi、Guy Bertrand
DOI:10.1002/anie.201507844
日期:2015.12
Cyclic (amino)(aryl)carbenes (CAArCs) result from the replacement of the alkyl substituent of cyclic (alkyl)(amino) carbenes (CAACs) by an aryl group. This structural modification leads to enhanced electrophilicity of the carbene center with retention of the high nucleophilicity of CAACs, and therefore CAArCs feature a small singlet–triplet gap. The isoindolium precursors are readily prepared in good