Synthese und Struktur von [CpFe(CO) 2 SO 2 ] + AsF 6 - / Synthesis and Structure of [CpFe(CO) 2 SO 2 ] + AsF 6

The cationic sulfur dioxide complexes [CpFe(CO) 2 SO 2 ] + AsF 6 - (7) and [CpCr(NO) 2 SO 2 ] + AsF 6 - (9) are obtained in almost quantitative yield from CpFe(CO) 2 I(CpCr(NO) 2 Cl) and AgAsF 6 in liquid SO 2 . With excess transition metal halide dinuclear halogen-bridged cations ([CpFe(CO) 2 IFe(CO) 2 Cp] + and [CpCr(NO) 2 ClCr(NO) 2 Cp] + ) are formed. The crystal structure of 7 is reported, and the bonding in the complexes is discussed in the light of spectroscopic data.