文摘
β-Diketiminate complexes of Tip>IIIp>-containing phosphanylphosphido ligands [p>Mep>NacnacTi(Cl){ηp>2p>-P(SiMe3)-PR2}] (p>Mep>Nacnacp>–p> = [Ar]NC(Me)CHC(Me)N[Ar]; Ar = 2,6-iPr2C6H3) were prepared by reactions of [p>Mep>NacnacTiCl2·THF] with lithium derivatives of diphosphanes R2P–P(SiMe3)Li (R = tBu, iPr) in toluene solutions. Surprisingly, reactions of [p>Mep>NacnacTiCl2·THF] with R2P–P(SiMe3)Li in THF solutions led to Tip>IVp> complexes containing phosphanylphosphinidene ligands [p>Mep>NacnacTi(Cl)(ηp>2p>-P-PtBu2)] via an autoredox path involving a migration of a nitrene NAr from the Nacnac skeleton to the Ti centers. Solid-state structures of [p>Mep>NacnacTi(Cl){ηp>2p>-P(SiMe3)-PtBu2}] (1a) and [p>Mep>NacnacTi(Cl)(ηp>2p>-P-PtBu2)] (two isomers 2a1, 2a2) together with [p>Mep>NacnacTi(Cl){ηp>2p>-P(SiMe3)-PiPr2}] (1b) and [p>Mep>NacnacTi(Cl)(ηp>2p>-P-PiPr2)] (2b) were established by the single-crystal X-ray diffraction and display clearly side-on geometry of the (Me3Si)P–PR2 and P–PR2 moieties in the solid state. Phosphanylphosphinidene complexes [p>Mep>NacnacTi(Cl)(ηp>2p>-P-PR2)] indicate that the p>31p>P NMR resonances of phosphinidene P atoms appear at a very low field in solution and in the solid state.