Ziółkowska A, Szynkiewicz N, Pikies J, Ponikiewski Ł
Department of Inorganic Chemistry, Chemical Faculty, Gdansk University of Technology, 11/12 Gabriela Narutowicza Str., 80-233 Gdansk, Poland.
Inorg Chem. 2020 Aug 17;59(16):11305-11315. doi: 10.1021/acs.inorgchem.0c00824. Epub 2020 Jul 31.
We present two important trends in the reactivity of the titanium complex [NacNacTi(Cl){η-P(SiMe)-PBu}] (NacNac = [Ar]NC(Me)CHC(Me)N[Ar]; Ar = 2,6-PrPh) with nucleophilic reagents RLi (R = PhP, BuO, (MeSi)N, and BuN) depending on the reaction medium. Reaction in nonpolar solvent (toluene) leads to three main products: via an autoredox process and nucleophilic substitution at the Ti-atom to afford the Ti(IV) complex [NacNacTi(R){η-P-PBu}] ( for R = PPh), via the elimination of MeSiR to afford Ti(III) complex [NacNacTi(Cl){η-P-PBu}][Li(12-crown-4)] (), and via 2e reduction process to afford new ionic complex [{ArNC(Me)CHC(Me)}Ti═NAr{η-P(SiMe)-PBu}][Li(12-crown-4)] (). Quite differently, the complex [NacNacTi(Cl){η-P(SiMe)-PBu}] reacts with PhPLi in THF, unexpectedly yielding two new, four-coordinate Ti(IV) imido complexes [{ArNC(Me)═CHC(H)(Me)-P(PBu)}Ti═NAr(Cl)][Li(12-crown-4)]·(toluene) and [{ArNC(CH)CH═C(Me)-P(PBu)}Ti═NAr(Cl)][Li(12-crown-4)]·(EtO). Complex dissolved in THF converts to and . , , , , and were characterized by X-ray diffraction. , , and were also fully characterized by multinuclear NMR spectroscopy.
我们展示了钛配合物[NacNacTi(Cl){η-P(SiMe)-PBu}]（NacNac = [Ar]NC(Me)CHC(Me)N[Ar]；Ar = 2,6-PrPh）与亲核试剂RLi（R = PhP、BuO、(MeSi)N和BuN）反应时的两个重要趋势，这取决于反应介质。在非极性溶剂（甲苯）中反应会产生三种主要产物：通过自氧化还原过程和在Ti原子上的亲核取代得到Ti(IV)配合物[NacNacTi(R){η-P-PBu}]（R = PPh时），通过消除MeSiR得到Ti(III)配合物[NacNacTi(Cl){η-P-PBu}][Li(12-冠-4)]（），以及通过2e还原过程得到新的离子配合物[{ArNC(Me)CHC(Me)}Ti═NAr{η-P(SiMe)-PBu}][Li(12-冠-4)]（）。截然不同的是，配合物[NacNacTi(Cl){η-P(SiMe)-PBu}]在THF中与PhPLi反应，意外地生成了两种新的四配位Ti(IV)亚胺基配合物[{ArNC(Me)═CHC(H)(Me)-P(PBu)}Ti═NAr(Cl)][Li(12-冠-4)]·(甲苯)和[{ArNC(CH)CH═C(Me)-P(PBu)}Ti═NAr(Cl)][Li(12-冠-4)]·(EtO)。溶解在THF中的配合物会转化为和。、、、、和通过X射线衍射进行了表征。、和也通过多核NMR光谱进行了全面表征。
