Ultrahigh chiral anisotropy factors in quasi-one-dimensional platinum compounds

Optically active, quasi-one-dimensional Pt-based compds. of the Magnus' green salt type [Pt(NH2R)4][PtCl4] where R denotes (S)-3,7-dimethyloctyl or (R)-2-ethylhexyl were synthesized. The optically active side groups in the corresponding complexes were found to induce CD (CD) in the dz2-pz transition between platinum atoms of adjacent coordination units. Interestingly, a bisignate Cotton effect was obsd., indicative of a helical structure of [Pt(NH2R)4][PtCl4]. The abs. values of the chiral anisotropy factors were of the order of 0.1, which is among the highest values reported for metal complexes. [on SciFinder (R)]