Copper(II) fluoride

Copper(II) fluoride is an inorganic compound with the chemical formula CuF₂. It is a white or green, crystalline solid that is used in various industrial applications, primarily in the manufacture of fluorine-containing chemicals and as a catalyst in organic synthesis. Copper(II) fluoride exists in two polymorphic forms, anhydrous and dihydrate (CuF₂·2H₂O), each with distinct physical and chemical properties.

Properties

Copper(II) fluoride, in its anhydrous form, is a highly hygroscopic substance, readily absorbing water from the atmosphere to form the dihydrate. The anhydrous form has a monoclinic crystal structure, while the dihydrate form is tetragonal. This compound is poorly soluble in water but dissolves in concentrated hydrochloric acid (HCl) and sulfuric acid (H₂SO₄).

Synthesis

Copper(II) fluoride can be synthesized by the reaction of copper(II) oxide (CuO) or copper(II) carbonate (CuCO₃) with hydrofluoric acid (HF): \[ \text{CuO} + 2 \text{HF} \rightarrow \text{CuF}_2 + \text{H}_2\text{O} \] \[ \text{CuCO}_3 + 2 \text{HF} \rightarrow \text{CuF}_2 + \text{CO}_2 + \text{H}_2\text{O} \] The dihydrate form can be obtained by crystallization from aqueous solutions of copper(II) fluoride.

Applications

Copper(II) fluoride is used in the synthesis of organofluorine compounds, serving as a source of fluorine. It acts as a catalyst in the preparation of fluorinated aromatic compounds through halogen exchange reactions. Additionally, it is employed in the production of fluoropolymers and in the fluorination of various organic compounds.

Safety

Copper(II) fluoride is considered toxic and must be handled with care. It is harmful if inhaled or ingested, causing irritation to the skin, eyes, and respiratory system. Proper personal protective equipment (PPE) and ventilation are required when working with this compound.

See Also

• Copper compounds
• Fluorine
• Catalysis
• Organofluorine chemistry