The Best of Both Worlds: Combining the Power of MICs and WCAs To Generate Stable and Crystalline Cr<sup>I</sup>‐Tetracarbonyl Complexes with <i>π</i>‐Accepting Ligands
Tobias Bens, Robert R. M. Walter, Julia Beerhues, Manuel Schmitt, Ingo Krossing, Biprajit Sarkar
Abstract
Abstract Here we present stable and crystalline chromium(I) tetracarbonyl complexes with pyridyl‐MIC (MIC=mesoionic carbene) ligands and weakly coordinating anions (WCA=[Al(OR F ) 4 ] − , R F =C(CF 3 ) 3 and BAr F =[B(Ar F ) 4 ] − , Ar F =3,5‐(CF 3 ) 2 C 6 H 3 ). The complexes were fully characterized via crystallographic, spectroscopic and theoretical methods. The influence of counter anions on the IR and EPR spectroscopic properties of the Cr I complexes was investigated, and the electronic innocence versus non‐innocence of WCAs was probed. These are the first examples of stable and crystalline [Cr(CO) 4 ] + complexes with a chelating accepting ligand, and the data presented here are of relevance for both the photochemical and the electrochemical properties of these classes of compounds.