HCOO

HCOO is a shorthand used in chemistry to denote the formate group, the conjugate base of formic acid (HCOOH). The formula HCOO− represents the formate anion, which occurs in salts such as sodium formate (NaHCOO) and potassium formate, and in esters of formic acid, generically written as HCOOR'.

Structure: The formate ion is resonance-stabilized, with charge delocalization over the two oxygens. The carbon is sp2-hybridized, giving a planar arrangement with the C–O bonds of intermediate length between typical single and double bonds. In coordination compounds, the two oxygens can bind metal centers as a bidentate ligand.

Occurrence and production: Formate arises from neutralization of formic acid or as a product of metabolism in living organisms. Industrially, formate salts are produced by neutralizing formic acid with minerals or bases. Formic acid and its salts have applications as buffering agents and in various chemical syntheses.

Reactions and uses: Formate esters (HCOOR') are important solvents and intermediates; formate ions can act as hydride donors in catalytic hydrogenation with suitable catalysts. Formates are also used in de-icing fluids and as supporting electrolytes; in biology, formate is a substrate for formate dehydrogenases and participates in one-carbon metabolism.

Safety: Formic acid is corrosive; formates generally pose lower hazard but can be irritants. Adequate ventilation and protective equipment are advised when handling formic acid or formate salts.