Rhodium(I) Complexes of the Conformationally Rigid IBioxMe_4 Ligand: Isolation of a Stable Low-Coordinate T?Shaped Complex

摘要

The isolation, characterization and reactivity of a T-shaped rhodium(I) complex containing Glorius’ bioxazoline derived N-heterocyclic carbene ligand IBioxMe_4 is described: [Rh(IBioxMe_4)_3][BAr~F_4] (1). 1 represents a rare example of a solution-stable “naked” 14-electron complex and is characterized in the solid state by highly distorted ligand geometries and Rh··· C distances >3.1 ? for the IBioxMe_4 alkyl substituents. Consistent with the bulky nature of the NHC ligand, no reaction was observed with excess IBioxMe_4, PCy_3, or norbornadiene. Reaction of 1 with CO, however, led to coordinatively saturated [Rh(IBioxMe_4)_3(CO)][BAr~F_4] (2).