Synthesis and Molecular Structure of [Fe 2 (μ‐P t Bu 2 ) 2 (NO) 4 ]

Reactions of the coordinatively unsaturated complexes [Fe 2 (μ‐P R 2 )(μ‐P R ′ 2 )(CO) 5 ] [ R = R ′ = t Bu ( 1 ); R = t Bu, R ′ = Cy ( 2 )] with nitric oxide in toluene at elevated temperatures were investigated. Thus, the new complexes [Fe 2 (μ‐P t Bu 2 ) 2 (NO) 4 ] ( 3 ) and [Fe 2 (μ‐P t Bu 2 )(μ‐PCy 2 )(NO) 4 ] ( 4 ) were obtained in good yields. The molecular structure of 3 was confirmed by X‐ray diffraction study. Compound 4 was also prepared from the coordinatively saturated species [Fe 2 (μ‐P t Bu 2 )(μ‐PCy 2 )(CO) 6 ] ( 2a ) with nitric oxide in refluxing toluene. Further closely related reactions at 60 °C with the complex 1 and [FeRu(μ‐P t Bu 2 ) 2 (CO) 5 ] ( 5 ), respectively, were investigated using preliminary crystal structure determination results.