Orthocarbonic acid

Orthocarbonic acid

Names
IUPAC name orthocarbonic acid
Systematic IUPAC name Methanetetrol[1] (substitutive)
Identifiers
CAS Number	463-84-3
3D model (Jmol)	Interactive image
ChemSpider	7826887
PubChem	9547954
InChI InChI=1S/CH4O4/c2-1(3,4)5/h2-5H Key: RXCVUXLCNLVYIA-UHFFFAOYSA-N
SMILES OC(O)(O)O
Properties
Chemical formula	CH4O4
Molar mass	80.04 g·mol^−1
Related compounds
Related compounds	Dihydroxymethylidene Silicic acid
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Infobox references

Orthocarbonic acid (methanetetrol) is the name given to a hypothetical compound with the chemical formula H₄CO₄ or C(OH)₄. 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 CO4−
4 (orthocarbonate), and is therefore considered an oxoacid of carbon.

Orthocarbonic acid is highly unstable, decomposing spontaneously into carbonic acid monohydrate:^[2][3]

H₄CO₄ → H₂CO₃ + H₂O.

Orthocarbonic acid is one of the group of carboxylic ortho acids that have the general structure of RC(OH)₃.The term ortho acid is also used to refer to the most hydroxylated acid in a set of oxoacids.

Orthocarbonate anions

By loss of one through four protons, orthocarbonic acid could yield four anions: H
3CO−
4, H
2CO2−
4, HCO3−
4, and CO4−
4.

As of 2002, salts of these anions had yet to be observed. However, theoretical studies suggest that Na₄CO₄ might be stable.^[4]

Orthocarbonate esters

The tetravalent moiety CO₄ is found in stable organic compounds; they are formally esters of orthocarbonic acid, and therefore are called orthocarbonates. For example, ethyl orthocarbonate can be prepared by the reaction between chloropicrin and sodium ethoxide in ethanol.^[5] Polyorthocarbonates are stable polymers that might have applications in absorbing organic solvents in waste treatment processes,^[6] or in dental restorative materials.^[7]

References

1. "Methanetetrol - PubChem Public Chemical Database". The PubChem Project. USA: National Center for Biotechnology Information.
2. Bohm S.; Antipova D.; Kuthan J. (1997). "A Study of Methanetetraol Dehydration to Carbonic Acid". International Journal of Quantum Chemistry. 62: 315–322. doi:10.1002/(SICI)1097-461X(1997)62:3<315::AID-QUA10>3.3.CO;2-N.
3. Carboxylic Acids and Derivatives IUPAC Recommendations on Organic & Biochemical Nomenclature
4. Al-Shemali Musstafa; Boldyre Alexander I (2002). "Search for Ionic Orthocarbonates: Ab Initio Study of Na₄CO₄". J. Phys. Chem. A. 106 (38): 8951–8954. doi:10.1021/jp020207+.
5. Orthocarbonic acid, tetraethyl ester Organic Syntheses, Coll. Vol. 4, p.457 (1963); Vol. 32, p.68 (1952)
6. Sonmez, H.B.; Wudl, F. (2005). "Cross-linked poly(orthocarbonate)s as organic solvent sorbents". Macromolecules. 38 (5): 1623–1626. doi:10.1021/ma048731x.
7. Stansbury, J.W. (1992). "Synthesis and evaluation of new oxaspiro monomers for double ring-opening polymerization". Journal of Dental Research. 71 (7): 1408–1412. doi:10.1177/00220345920710070901. PMID 1629456. Retrieved 2008-06-19.