Crystal structure of a tri-fluoro-methyl benzoato quadruple-bonded dimolybdenum complex.

The study of quadruple bonds between transition metals, in particular those of dimolybdenum, has revealed much about the two-electron bond. The solid-state structure of the quadruple-bonded dimolybdenum(II) complex tetra-kis-[μ-4-(tri-fluoro-methyl)-benzoato-κ 2 O : O ']bis[(tetra-hydro-furan-κ O )molybdenum(II)] 0.762-pentane 0.238-tetra-hydro-furan solvate, [Mo 2 ( p -O 2 CC 6 H 4 CF 3 ) 4 ·2THF]·0.762C 5 H 12 ·0.238C 4 H 8 O or [Mo 2 (C 8 H 4 F 3 O 2 ) 4 (C 4 H 8 O) 2 ]·0.762C 5 H 12 ·0.238C 4 H 8 O is reported. The complex crystallizes within a triclinic cell and low symmetry ( P ) results from the inter-calated penta-ne/THF solvent mol-ecules. The paddlewheel structure at 100 K has inversion symmetry and comprises four bridging carboxyl-ate ligands encases the Mo 2 (II,II) core that is characterized by two axially coordinated THF mol-ecules and an Mo-Mo distance of 2.1098 (7) Å.