Trifluoromethylation of [AuF<sub>3</sub>(SIMes)]: Preparation and Characterization of [Au(CF<sub>3</sub>)<sub><i>x</i></sub>F<sub>3−<i>x</i></sub>(SIMes)] (<i>x=</i>1–3) Complexes
Marlon Winter, Niklas Limberg, Mathias A. Ellwanger, Alberto Pérez‐Bitrián, Karsten Sonnenberg, Simon Steinhauer, Sebastian Riedel
Abstract
Abstract Trifluoromethylation of [AuF 3 (SIMes)] with the Ruppert–Prakash reagent TMSCF 3 in the presence of CsF yields the product series [Au(CF 3 ) x F 3− x (SIMes)] ( x= 1–3). The degree of trifluoromethylation is solvent dependent and the ratio of the species can be controlled by varying the stoichiometry of the reaction, as evidenced from the 19 F NMR spectra of the corresponding reaction mixtures. The molecular structures in the solid state of trans ‐[Au(CF 3 )F 2 (SIMes)] and [Au(CF 3 ) 3 (SIMes)] are presented, together with a selective route for the synthesis of the latter complex. Correlation of the calculated SIMes affinity with the carbene carbon chemical shift in the 13 C NMR spectrum reveals that trans ‐[Au(CF 3 )F 2 (SIMes)] and [Au(CF 3 ) 3 (SIMes)] nicely follow the trend in Lewis acidities of related organo gold(III) complexes. Furthermore, a new correlation between the Au−C carbene bond length of the molecular structure in the solid state and the chemical shift of the carbene carbon in the 13 C NMR spectrum is presented.