Tuning electronic structure through halide modulation of mesoionic carbene cobalt complexes

The first examples of Co( ii ) mesoionic carbene complexes (CoX 2 Dipp MIC 2 ; X = Cl − , Br − , I − ) demonstrate a new electronic perturbation on tetrahedral Co( ii ) complexes. Using absorption spectroscopy and magnetometry, the consequences of the MIC's strong σ-donating/minimal π-accepting nature are analyzed and shown to be further tunable by the nature of the coordinated halide. The first examples of Co( ii ) mesoionic carbene complexes (CoX 2 Dipp MIC 2 ; X = Cl − , Br − , I − ) demonstrate a new electronic perturbation on tetrahedral Co( ii ) complexes.