The Cu(2+) ions in the title compounds, namely bis[1,3-bis(pentafluorophenyl)propane-1,3-dionato-κ(2)O,O']copper(II) p-xylene n-solvate, [Cu(C15HF10O2)2]·nC8H10, with n = 1, (I), n = 2, (II), and n = 4, (III), are coordinated by two 1,3-bis(pentafluorophenyl)propane-1,3-dionate ligands. The coordination complexes of (I) and (II) have crystallographic inversion symmetry at the Cu atom and the p-xylene molecule in (I) also lies across an inversion centre. The p-xylene molecules in (I) and (II) interact with the pentafluorophenyl groups of the complex via arene-perfluoroarene interactions. In the crystal of (III), two of the p-xylene molecules interact with the pentafluorophenyl groups via arene-perfluoroarene interactions. The other two p-xylene molecules are located on the CuO4 coordination plane, forming a uniform cavity produced by metal···π interactions.
Keywords: 1,3-bis(pentafluorophenyl)propane-1,3-dionate; arene–perfluoroarene interactions; copper complexes; crystal structure; metal...π interactions; pseudopolymorphs; variable solvation.