Dppa als Komplexligand: Metall-Koordination und P-N-Spaltung in Komplexen des Typs [CpM(L)dppa]X (M = Fe, Mn; L = CO, NO) / Dppa as a Ligand: Metal Coordination and P-N Cleavage in Complexes of the Type [CpM(L)dppa]X (M = Fe, Mn; L = CO, NO)
Abstract The reactions of [CpMn(CO)2(NO)]BF4 or CpFe(CO)2Cl with PPh2NHR (R = Ph, PPh2) lead to the salts [CpML(CO)PPh2NHR]X with monodentate aminophosphine ligands. In the case of R = PPh2 (= dppa) the complexes [CpML(dppa)]X with bidentate dppa are also formed. The salt [CpFe(CO)(dppa)]Cl can be deprotonated to give the neutral complex CpFe(CO){(PPh2)2N)} with the diphosphinoamide ligand, which can be N-alkylated by Mel to afford [CpFe(CO){(PPh2)2NMe}]I. The complex [CpMn(NO)(dppa)]BF4 undergoes a P-N cleavage reaction by the solvent methanol to form [CpMn(NO)(PPh2NH2)(PPh2OMe)]BF4. The non-chelated complexes [CpFe(CO)2PPh2NHR]Cl are deprotonated by DBU to give the neutral ferrioiminophosphoranes CpFe(CO)2PPh2 = NR. For R = PPh2 photolysis leads to CO-elimination and to CpFe(CO)(PPh2NPPh2). CpFe(CO)2PPh2NPPh2 can be alkylated by Mel or metallated by CpFe(CO)2Cl to form [CpFe(CO)2PPh2NPPh2Me]I or [CpFe(CO)2PPh2NPPh2(CO)2FeCp]Cl, respectively. Oxidation of CpFe(CO)2PPh2NPPh2 is possible by (SiMe3)2O2, sulfur, or selenium to lead to the neutral complexes CpFe(CO)2PPh2=NPPh2 = E (E = O, S, Se) with a heterodiene system. The IR and NMR spectra of all species as well as the X-ray structures of the complexes [CpFe(CO)dppa]Cl, [CpMn(NO)dppa]BF4 and [CpMn(NO)(PPh2NH2)(PPh2OMe)]BF4 are reported and discussed.