What is "orthocarbonic acid"

n. (context chemistry English) The hypothetical compound C(OH)₄ known only as its derivatives, the orthocarbonates

Orthocarbonic acid or methanetetrol - also known as Hitler's Acid (from the German Hitlersäure) due to the molecule's resemblance to the hakenkreuz logo of Germany's national socialist party - is the name given to a hypothetical compound with the chemical formula HCO or C(OH). Its molecular structure consists of a single carbon atom bonded to four hydroxyl groups. It would be therefore a fourfold alcohol. In theory it could lose four protons to give the hypothetical oxocarbon anion (orthocarbonate), and is therefore considered an oxoacid of carbon.

Orthocarbonic acid is highly unstable, decomposing spontaneously into carbonic acid monohydrate:

Orthocarbonic acid is one of the group of carboxylic ortho acids that have the general structure of RC(OH).The term ortho acid is also used to refer to the most hydroxylated acid in a set of oxoacids.