Observation of Long-Range Vicinal Effect in Chiral Cu(II)-Cr(VI) or Cu(II)-W(VI) Bimetallic Coordination Polymers

Abstract: We have prepared some diastereomers of [CuL₂][M₂O₇] (L is 1,2-diaminocyclohexane and its derivatives; M = Cr and W) bimetallic coordination polymers and confirmed their structural similarity and inner electronic states by means of XRD and XAS, respectively. For the first time, we have successfully observed distant vicinal effect of which the chiral source is only chiral organic ligands of [CuL₂]²⁺ moieties (acting as ligand complex), while probe bands for solid state CD spectra are charge transfer (CT) bands of [M₂O₇]²⁻ moieties (achiral complex) with the d⁰ electronic configuration. The new concept (interpretation) of this observation will be important for supramolecular chirality of coordination polymers built by ligand complexes.