Formate (

IUPAC The International Union of Pure and Applied Chemistry (IUPAC ) is an international federation of National Adhering Organizations working for the advancement of the chemical sciences, especially by developing nomenclature and terminology. It is ...

name: methanoate) is the

conjugate base A conjugate acid, within the Brønsted–Lowry acid–base theory, is a chemical compound formed when an acid donates a proton () to a base—in other words, it is a base with a hydrogen ion added to it, as in the reverse reaction it loses a ...

formic acid Formic acid (), systematically named methanoic acid, is the simplest carboxylic acid, and has the chemical formula HCOOH and structure . It is an important intermediate in chemical synthesis and occurs naturally, most notably in some ants. Est ...

. Formate is an

anion An ion () is an atom or molecule with a net electrical charge. The charge of an electron is considered to be negative by convention and this charge is equal and opposite to the charge of a proton, which is considered to be positive by conve ...

() or its derivatives such as

ester In chemistry, an ester is a compound derived from an oxoacid (organic or inorganic) in which at least one hydroxyl group () is replaced by an alkoxy group (), as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides ...

. The salts and esters are generally colorless.Werner Reutemann and Heinz Kieczka "Formic Acid" in ''Ullmann's Encyclopedia of Industrial Chemistry'' 2002, Wiley-VCH, Weinheim.

Fundamentals

When dissolved in water, formic acid converts to formate: : Formate is a planar anion. The two oxygen atoms are equivalent and bear a partial negative charge. The remaining C-H bond is not acidic.

Biochemistry

: Formate is a common C-1 source in living systems. It is formed from many precursors including choline,

serine Serine (symbol Ser or S) is an α-amino acid that is used in the biosynthesis of proteins. It contains an α- amino group (which is in the protonated − form under biological conditions), a carboxyl group (which is in the deprotonated − for ...

, and sarcosine. It provides a C-1 source in the biosynthesis of some

nucleic acid Nucleic acids are biopolymers, macromolecules, essential to all known forms of life. They are composed of nucleotides, which are the monomers made of three components: a 5-carbon sugar, a phosphate group and a nitrogenous base. The two main ...

s. Formate (or formic acid) is ina leaving group in the demethylation of some

sterol Sterol is an organic compound with formula , whose molecule is derived from that of gonane by replacement of a hydrogen atom in position 3 by a hydroxyl group. It is therefore an alcohol of gonane. More generally, any compounds that contain the go ...

s.. These conversions are catalyzed by aromatase

enzyme Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products ...

s using O₂ as the oxidant. Specific conversions include

testosterone Testosterone is the primary sex hormone and anabolic steroid in males. In humans, testosterone plays a key role in the development of male reproductive tissues such as testes and prostate, as well as promoting secondary sexual characteristi ...

to estradiol and

androstenedione Androstenedione, or 4-androstenedione (abbreviated as A4 or Δ4-dione), also known as androst-4-ene-3,17-dione, is an endogenous weak androgen steroid hormone and intermediate in the biosynthesis of estrone and of testosterone from dehy ...

to estrone. Formate reversibly oxidized by the enzyme

formate dehydrogenase Formate dehydrogenases are a set of enzymes that catalyse the oxidation of formate to carbon dioxide, donating the electrons to a second substrate, such as NAD+ in formate:NAD+ oxidoreductase () or to a cytochrome in formate:ferricytochrome-b1 ox ...

from '' Desulfovibrio gigas'': :

Formate esters

Formate esters have the formula HCOOR (alternative way of writing formula ROC(O)H or RO₂CH). 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

Methanol Methanol (also called methyl alcohol and wood spirit, amongst other names) is an organic chemical and the simplest aliphatic alcohol, with the formula C H3 O H (a methyl group linked to a hydroxyl group, often abbreviated as MeOH). It is ...

and

carbon monoxide Carbon monoxide ( chemical formula CO) is a colorless, poisonous, odorless, tasteless, flammable gas that is slightly less dense than air. Carbon monoxide consists of one carbon atom and one oxygen atom connected by a triple bond. It is the simpl ...

react in the presence of a strong base, such as sodium methoxide: :CH3OH + CO -> HCOOCH3 Hydrolysis of methyl formate gives formic acid and regenerates methanol: :HCOOCH3 -> HCOOH + CH3OH Formic acid is used for many applications in industry. Formate esters often are fragrant or have distinctive odors. Compared to the more common acetate esters, formate esters are less commonly used commercially because they are less stable.Johannes Panten and Horst Surburg "Flavors and Fragrances, 2. Aliphatic Compounds" in Ullmann's Encyclopedia of Industrial Chemistry, 2015, Wiley-VCH, Weinheim. Ethyl formate is found in some confectionaries.

Formate salts

Formate salts have the formula M(O₂CH)(H₂O)_''x''. 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 Hydrogenation is a chemical reaction between molecular hydrogen (H2) and another compound or element, usually in the presence of a catalyst such as nickel, palladium or platinum. The process is commonly employed to reduce or saturate organic ...

catalysts.

Examples

* ethyl formate, CH₃CH₂(HCOO) * sodium formate, Na(HCOO) * potassium formate, K(HCOO) *

caesium formate Formate (IUPAC name: methanoate) is the conjugate base of formic acid. Formate is an anion () or its derivatives such as ester of formic acid. The salts and esters are generally colorless.Werner Reutemann and Heinz Kieczka "Formic Acid" in ''Ull ...

, Cs(HCOO); see Caesium: Petroleum exploration * methyl formate, CH₃(HCOO) *

methyl chloroformate Methyl chloroformate is the methyl ester of chloroformic acid. It is an oily colorless liquid, although aged samples appear yellow. It is also known for its pungent odor. Preparation Methyl chloroformate can be synthesized using methanol and ...

, CH₃OCOCl * triethyl orthoformate *

trimethyl orthoformate Trimethyl orthoformate (TMOF) is the organic compound with the formula HC(OCH3)3. A colorless liquid, it is the simplest orthoester. It is a reagent used in organic synthesis for the formation of methyl ethers. The product of reaction of an ald ...

, C₄H₁₀O₃ *

phenyl formate In organic chemistry, the phenyl group, or phenyl ring, is a cyclic group of atoms with the formula C6 H5, and is often represented by the symbol Ph. Phenyl group is closely related to benzene and can be viewed as a benzene ring, minus a hydroge ...

HCOOC₆H₅ * amyl formate

References

{{Reflist Carboxylate anions de:Formiate