Mixed metalII–metalIV hybrid fluorides

Six MII–MIV type II hybrid fluorides (MII = Cu, Ni; MIV = Si, Ti, Mo) are compared: (Ni(en)3)·(TiF6), [Hpy]2·(Cu(py)4(MF6)2) (MIV = Ti, Mo), [H3O]2·(SiF6(CuF(py)4)2)·(F)2 and Cu(en)2MF6 (MIV = Ti, Si). They are obtained at 160 °C under microwave heating and the structures are determined either from single crystal or powder X-ray diffraction data. All phases involve neutral amines that are linked to MII cations, a feature of type II hybrids. In (Ni(en)3)·(TiF6), the cationic (Ni(en)3)2+ and anionic (TiF6)2− entities are isolated. In [Hpy]2·(Cu(py)4(TiF6)2) and [Hpy]2·(Cu(py)4(MoF6)2), extra non metal bonded amines are protonated to give [Hpy]+ cations that exchange hydrogen bonds with fluoride anions, a feature of type I hybrids. All phases exhibit a fully fluorinated octahedral environment of MIV cations, at the opposite from previously reported [H3O]2·(NbOF5(CuF(py)4)2)·(F)2 or [Hpy]2·(Cu(py)4)(MoO2F4)2. In [Hpy]2·(Cu(py)4(MF6)2) (MIV = Ti, Mo) or [H3O]2·(SiF6(CuF(py)4)2)·(F)2, CuII and MIV entities are associated by fluoride anions to give anionic or neutral trimetallic clusters, respectively; the results of thermal analysis suggest that the oxidation state is +IV for molybdenum and it is proposed that H3O+ and “free” F− ion pairs can be replaced locally by H2O and HF couples. In Cu(en)2MF6, the CuII and MIV entities alternate and build infinite chains