BaF-benzenedicarboxylate: the first mechanochemical synthesis of a new coordination polymer with a direct Ba–F bond

A new barium coordination polymer, BaF-benzenedicarboxylate (BaF(p-BDC)_0.5), with fluorine directly coordinated to the metal cation, was prepared by mechanochemical synthesis routes. Phase-pure BaF-benzenedicarboxylate was synthesized by milling starting either from barium hydroxide or from barium acetate as sources for barium cations. In both cases, the second reactant was 1,4-benzenedicarboxylic acid (H₂(p-BDC)). Ammonium fluoride was used as fluorinating agent directly at milling. This is the first mechanochemical synthesis of coordination polymers where fluorine is directly coordinated to the metal cation. Following the second possibility, barium acetate fluoride (Ba(OAc)F) is formed as intermediate product after milling, and the new coordination polymer is accessible only after washing with water and dimethyl sulfoxide. The new compound BaF(p-BDC)_0.5 was characterized by X-ray powder diffraction, FTIR-, and ¹⁹F, ¹H-¹³C CP MAS NMR spectroscopies, DTA-TG, and elemental analysis.