Sodium Fluoroborate, also known as sodium tetrafluoroborate

Sodium Fluoroborate, also known as sodium tetrafluoroborate with the chemical formula NaBF4, is an inorganic compound that forms colorless or white water-soluble rhombic crystals. It is readily soluble in water with a solubility of 108 g/100 mL, but less soluble in organic solvents. This compound has a molecular weight of 109.79 and a melting point ranging from 384°C to 406°C. It is sensitive to moisture and gradually decomposes upon heating.

Industrially, Sodium Fluoroborate is utilized in various applications such as a catalyst in the synthesis of bis(indolyl)methanes through electrophilic substitution reactions involving indoles with ketones and aldehydes. It also serves as a source of the tetrafluoroborate anion in the synthesis of ionic liquids, including 1-butyl-3-methylimidazolium tetrafluoroborate and trihexyl(tetradecyl)phosphonium tetrafluoroborate. Additionally, it is used in the laboratory synthesis of boron fluoride and in the production of fluoroheterocyclic and fluoro-nucleic acids. The compound is also employed in metal finishing, fluxes, and plating circuits.

Safety is a critical consideration with Sodium Fluoroborate. It is moderately toxic by the subcutaneous route and emits toxic fumes of fluoride and sodium oxide when heated to decomposition. It is important to handle this compound with appropriate personal protective equipment, including eye shields, gloves, and N95 or P1 type respirator filters. Storage should be in a cool, dry place with containers kept tightly closed, and it is advised to store it under inert gas to prevent moisture absorption. In case of fire, it is recommended to use water mist, alcohol-resistant foam, dry powder, or carbon dioxide for extinguishing. Spills should be cleaned up by sweeping or shoveling into appropriate closed containers for disposal, with care taken to prevent the product from entering sewer systems.