Controlled introduction of functional groups at one P atom in [Cp*Fe(η(5)-P(5))] and release of functionalised phosphines

By salt metathesis reactions of the anionic complexes of the type [Cp*Fe(η(4)-P(5)R)](−) (R = (t)Bu (1a), Me (1b), –C[triple bond, length as m-dash]CPh (1c); Cp* = 1,2,3,4,5-pentamethylcyclopentadienyl) with organic electrophiles (XR(FG); X = halogen; R(FG) = (CH(2))(3)Br, (CH(2))(4)Br, Me) a variety of organo-substituted polyphosphorus ligand complexes of the type [Cp*Fe(η(4)-P(5)RR(FG))] (2) are obtained. Thereby, organic substituents with different functional groups (FG), such as halogens or nitriles, are introduced. In [Cp*Fe(η(4)-P(5)RR′)] (2a: R = (t)Bu, R′ = (CH(2))(3)Br), the bromine substituent can be easily substituted, leading to functionalized complexes [{Cp*Fe(η(4)-P(5)tBu)}(CH(2))(3){Cp*Fe(η(4)-P(5)Me)}] (4) and [Cp*Fe(η(4)-P(5)RR′)] (5) (R = (t)Bu, R′ = (CH(2))(3)PPh(2)) or by abstraction of a phosphine to the asymmetric substituted phosphine tBu(Bn)P(CH(2))(3)Bn (6). The reaction of the dianionic species [K(dme)(2)](2)[Cp*Fe(η(4)-P(5))] (I’) with bromo-nitriles leads to [Cp*Fe{η(4)-P(5)((CH(2))(3)CN)(2)}] (7), allowing the introduction of two functional groups attached to one phosphorus atom. 7 reacts with ZnBr(2) in a self-assembly reaction to form the supramolecular compound [Cp*Fe{η(4)-P(5)((CH(2))(3)CN)(2)}ZnBr(2)](n) (8).