Dimolybdenum Perfluorotetrabenzoate and Silver Perfluorocyclohexanoate: Synthesis, Evaporation, and Thermodynamic Characteristics

Anhydrous dimolybdenum perfluorotetrabenzoate Мо2(ООСС6F5)4 (I) and silver perfluorocyclohexanoate AgOOCC6F11 (II) are synthesized for the first time. Complex I is synthesized by the transcarboxylation of dimolybdenum tetraacetate with pentafluorobenzoic acid. Compound II is synthesized from freshly prepared silver oxide and perfluorocyclohexanoic acid. The evaporation of the complexes is studied by the Knudsen method with mass spectral analysis of the gas phase. The sublimation of Мо2(ООСС6F5)4 is congruent. The enthalpy of sublimation and the equation of the temperature dependence of the vapor pressure are found. The evaporation of AgOOCC6F11 is accompanied by the complete thermal decomposition with the formation of Ag(s) and mainly С6F12, С6F10, and CO2 molecules. The standard enthalpies of thermal decomposition ( Δ_rH_298.15^^∘ (5) = 439.5 ± 16.4 kJ/mol, Δ_rH_298.15^^∘ (6) = 325.2 ± 14.0 kJ/mol) and formation of the silver complex ( Δ_fH_298.15^^∘ (AgOOCC6F11, c) = –2751.0 ± 24.4 kJ/mol) are determined.