Synthesis and Characterisation of Low‐Coordinate Transition‐Metal Complexes Stabilised by Sterically Demanding Carbazolido Ligands

The synthesis and characterisation of the homoleptic transition‐metal complexes (1,8‐Ph 2 ‐3,6‐Me 2 C 12 H 4 N) 2 M (M = Cr, 1 ; M = Mn, 2 ; M = Fe, 3 ; M = Co, 4 ) are described. Formally two‐coordinate, the solid‐state structures of 2 and 3 reveal near‐linear N–M–N geometries and significant bending of the flanking phenyl groups towards the metal centres. Solid‐state magnetic measurements reveal high spin metal centres in 1 – 4 ; computational calculations for the model complexes M(1,8‐Ph 2 C 12 H 6 N) 2 (M = Cr–Co) confirm the presence of high‐spin configurations within these bis‐carbazolido compounds and an orbital ordering of δ < π < σ for these systems.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)