Reaction Of UO2(O2CCH3)2 with pentafluorobenzoic acid yields UO2(O2CC6F5)2, which has been converted into the solvated complexes UO2(O2CC6F5)2L2·S [L2 = 2,2′-bipyridyl (bpy), S = 0.33 (PhH) or 0.07 (t-BuOH); L = Ph3PO, S = t-BuOH; L = Ph3AsO, S = 0.40 (t-BuOH)] and the solvent free UO2(O2CC6F5)2L2 [L2 = bpy; L = Ph3PO]. The crystal structure of UO2(O2CC6F5)2bpy (orthorhombic, space group P212121; a = 18.45(2), b = 18.94(2), c = 7.069(8) Å, Z = 4] reveals distorted hexagonal bipyramidal stereochemistry with a trans UO2 group, chelating pentafluorobenzoate ligands, and chelating 2,2′-bipyridyl, which is significantly displaced from the hexagonal plane. The structure of UO2(O2CC6F5)2(OPPh3)2·t-BuOH [rhombohedral, space group R3; a = 21.51(3) Å, α = 117.28(5)°, Z = 3] shows trans UO2, pseudo trans Ph3PO ligands, and one unidentate and one disordered chelating pentafluorobenzoate ligand, whilst t-BuOH could not be located because it is highly disordered. Relationships between ν (CO2) frequencies and the carboxylate coordination are discussed, and UO2(O2CC6F5)2(OAsPh3)2.0.40 (t-BuOH) is considered to have stereochemistry similar to that of the phosphine oxide complex. The complexes undergo decarboxylation in dimethyl sulphoxide yielding pentafluorobenzene and carbonatodioxouranium(VI) species not UO2(C6F5)2 derivatives.