Nonaqueous synthesis of molecular zinc amide phosphate

Three new molecular zinc compounds were prepared by nonaqueous reactions of Zn[N(SiMe3)2]2 and ZnEt2 with trimethylsilylesters of phosphoric acid, OP(OSiMe3)3 and OP(OSiMe3)2(OH). Single-crystal X-ray diffraction analyses of crystalline products revealed molecular structures of two mononuclear complexes [ZnX2OP(OSiMe3)3] (X = N(SiMe3)2 (1), hfacac = hexafluoroacetylacetonate, (2)) and one dinuclear zinc phosphate [(Zn{(py)N(SiMe3)2}{μ2-O2P(OSiMe3)2})2] (3). Compound 1 is only the second structurally characterized adduct of zinc bisamide with an oxygen donor and a three-coordinate Zn atom. The cyclic inorganic core {Zn(μ2-O2PO2)}2 in 3 is a model for the most common single four-ring (S4R) building unit of open-framework zinc phosphates. The molecule of 3 possesses reactive amide and trimethylsiloxy groups that can be employed in further studies on the formation of extended structures by condensation reactions. Spectroscopic properties and thermal behavior of the molecular products were examined. Compounds 1 and 3 were converted to α-Zn2P2O7 by calcination.