Formate


Formate is the anion derived from formic acid. Its formula is represented in various equivalent ways: HCOO− or CHOO− or HCO2−. It is the product of deprotonation of formic acid. It is the simplest carboxylate anion. A formate is a salt or ester of formic acid.

Biochemistry

Formate is reversibly oxidized by the enzyme formate dehydrogenase from Desulfovibrio gigas:

Formate esters

Formate esters have the formula ROCH. Many form spontaneously when alcohols dissolve in formic acid.
The most important formate ester is methyl formate, which is produced as an intermediate en route to formic acid. Methanol and carbon monoxide react in the presence of a strong base, such as sodium methoxide:
Hydrolysis of methyl formate gives formic acid and regenerates methanol:
Formic acid is used for many applications in industry.
Formate esters often are fragrant or have distinctive odors. Compared to the more common ethyl esters, formate esters are less commonly used commercially because they are less stable. Ethyl formate is found in some confectionaries.

Formate salts

Formate salts have the formula Mx. Such salts are prone to decarboxylation. For example, hydrated nickel formate decarboxylates at about 200 °C to give finely powdered nickel metal:
Such fine powders are useful as hydrogenation catalysts.

Examples