Combining ligand-enhanced backdonation and steric shielding to stabilize a mono-substituted Au(I) carbene

A mono-substituted Au(I) carbene was prepared by reacting HC(N-2)(Dmp) (Dmp = 2,6-dimesitylphenyl) with an (o-carboranyl)-diphosphine AuNTf2 complex. It is stable up to similar to 10 degrees C and was characterized by NMR spectrocopy. According to DFT calculations, the chelating P<^>P ligand enhances Au -> C-carb backdonation, while the Dmp substituent provides kinetic stabilization but does not bias the electronic structure of the carbene complex.

Automated summary

A mono-substituted Au(I) carbene was synthesized by reacting HC(N-2)(Dmp) (Dmp = 2,6-dimesitylphenyl) with an (o-carboranyl)-diphosphine AuNTf2 complex. It exhibited stability up to about 10 degrees C and its structure was determined using NMR spectroscopy. Density functional theory calculations revealed that the chelating P<^>P ligand enhanced Au -> C-carb backdonation, while the Dmp substituent provided kinetic stabilization without altering the electronic structure of the carbene complex.