Synthesis and Characterization of a Manganese(III) Complex with a Tetradentate N-Heterocyclic Carbene Ligand

An imidazolium salt, containing two aryloxy groups, was prepared as a precursor for the tetradentate dicarbene ligand. The complexation with Mn(OAc)₂ gave an air-stable Mn(III) N-heterocyclic carbene complex in moderate yield. The crystal structure of the complex shows a distorted-square-pyramidal structure, in which two carbene carbon atoms and two aryloxy oxygen atoms of the tetradentate carbene ligand occupied the basal plane.