Synthesis and Properties of Polyether Adducts of Hexafluoropentanedionatosilver(I)

A series of polyether [CH3O(CH2CH2O)mCH3, with m = 2 (diglyme), 3 (triglyme), 4 (tetraglyme)] mono- or hemiadducts of hexafluoropentanedionatosilver(I) have been synthesized and in selected cases structurally characterized. Decomposition of [Ag(hfa)(diglyme)]2 (hfa = hexafluoropentanedionato) in air affords a mixture of products including crystals of [Ag2(hfa)(O2CCF3)(diglyme)2]. The structure of [Ag(hfa)(diglyme)]2 consists of two silver cations which are bridged by four oxygens from two hfa ligands; each Ag(I) ion is also coordinated to a chelating diglyme molecule. In comparison, ligation of a longer polyether chain results in a monomeric species [Ag(hfa)(tetraglyme)]. The compounds are soluble in a range of solvents including supercritical carbon dioxide (scCO2). Crystal data for [Ag(hfa)(diglyme)]2 (150 K): a = 21.376(3) Å, b = 8.4143(17) Å, c = 21.067(3) Å, β = 124.05(1)°, monoclinic space group C2/c; Z = 8. Crystal data for [Ag2(hfa)(O2CCF3)(diglyme)2] (150 K): a = 9.0945(12) Å, b = 9.4110(13) Å, c = 17.803(2) Å, α = 96.109(14)°, β = 101.649(13)°, γ = 105.06(2)°, triclinic space group P1̄; Z = 2. Crystal data for [Ag(hfa)(tetraglyme)] (150 K): a = 14.152(3) Å, b = 16.996(3) Å, c = 8.620(2) Å, β = 106.99(2)°, monoclinic space group P21/c; Z = 4.