Orthoformic acid or methanetriol is a hypothetical compound with the formula HC(OH)₃. In this molecule, the central carbon is bound to one hydrogen

Hydrogen

Hydrogen is the chemical element with atomic number 1. It is represented by the symbol H. With an average atomic weight of , hydrogen is the lightest and most abundant chemical element, constituting roughly 75% of the Universe's chemical elemental mass. Stars in the main sequence are mainly...

 and three hydroxyl

Hydroxyl

A hydroxyl is a chemical group containing an oxygen atom covalently bonded with a hydrogen atom. In inorganic chemistry, the hydroxyl group is known as the hydroxide ion, and scientists and reference works generally use these different terms though they refer to the same chemical structure in...

 groups.

Ortoformic acid has not been isolated to date, and is believed to be unstable, decomposing into water

Water

Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...

 and formic acid

Formic acid

Formic acid is the simplest carboxylic acid. Its chemical formula is HCOOH or HCO2H. It is an important intermediate in chemical synthesis and occurs naturally, most notably in the venom of bee and ant stings. In fact, its name comes from the Latin word for ant, formica, referring to its early...

.

Esters

Methanetriol ester

Ester

Esters are chemical compounds derived by reacting an oxoacid with a hydroxyl compound such as an alcohol or phenol. Esters are usually derived from an inorganic acid or organic acid in which at least one -OH group is replaced by an -O-alkyl group, and most commonly from carboxylic acids and...

s, known as orthoformates, are well known and commercially available. Like acetal

Acetal

An acetal is a molecule with two single-bonded oxygen atoms attached to the same carbon atom.Traditional usages distinguish ketals from acetals...

s, they are stable towards bases but easily hydrolyzed in acidic conditions to the alcohol and an ester of formic acid. They are used are as mild dehydrating agent. Especially well known are trimethyl orthoformate

Trimethyl orthoformate

Trimethyl orthoformate is a the simplest orthoester. It is a reagent used in organic synthesis for the introduction of a protecting group for aldehydes. The product of reaction of an aldehyde with trimethyl orthoformate is an acetal...

, triethyl orthoformate

Triethyl orthoformate

Triethyl orthoformate is an orthoester of formic acid. It is commercially available. The industrial synthesis is from hydrogen cyanide and ethanol.It may also be prepared from the reaction of sodium ethoxide and chloroform:...

, and triisopropyl orthoformate.