Paramagnetisches [(CO) 5CrCNFe(dppe)Cp]BF 4, eine gemischtvalente metallorganische Verbindung

Abstract

The red closed-shell diamagnetic complex (CO) 5CrCNFe(dppe)Cp ( 1) is obtained from Na[Cr(CO) 5CN] and Cp(dppe)FeBr. Oxidation with [( p-BrC 6H 4) 3N]BF 4 converts it into the dark brown paramagnetic title compound 2. The crystal structure of 2, featuring a close to linear CrCNFe arrangement, shows no unusual molecular details related to the odd-electron nature of the complex. Spectroscopic data of 2, including a strong IT band at 1130 nm, indicate that 2 is a heterometallic mixed valence complex of class II with a high degree of delocalization.