Allophanic acid

Last updated
Allophanic acid
Allophanic acid.svg
Names
Preferred IUPAC name
Carbamoylcarbamic acid
Identifiers
3D model (JSmol)
1756623
ChEBI
ChemSpider
KEGG
PubChem CID
UNII
  • InChI=1S/C2H4N2O3/c3-1(5)4-2(6)7/h(H,6,7)(H3,3,4,5)
    Key: AVWRKZWQTYIKIY-UHFFFAOYSA-N
  • C(=O)(N)NC(=O)O
Properties
C2H4N2O3
Molar mass 104.065 g·mol−1
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Allophanic acid is the organic compound with the formula H2NC(O)NHCO2H. It is a carbamic acid, the carboxylated derivative of urea. Biuret can be viewed as the amide of allophanic acid.

Treating urea with sodium bicarbonate is claimed to give allophanic acid: [1]

H2NC(O)NH2 + NaHCO3 → H2NC(O)NHCO2H + NaOH

Although allophanic acid per se may not have been purified, its conjugate base, H2NC(O)NHCO2, allophanate is well known. Salts of this anion have been characterized by X-ray crystallography. [2] [3] The allophanate anion is the substrate for the enzyme allophanate hydrolase.

Allophanate esters arise from the condensation of carbamates.

Allophanat-Bildung.png

Related Research Articles

<span class="mw-page-title-main">Alkali metal</span> Group of highly reactive chemical elements

The alkali metals consist of the chemical elements lithium (Li), sodium (Na), potassium (K), rubidium (Rb), caesium (Cs), and francium (Fr). Together with hydrogen they constitute group 1, which lies in the s-block of the periodic table. All alkali metals have their outermost electron in an s-orbital: this shared electron configuration results in their having very similar characteristic properties. Indeed, the alkali metals provide the best example of group trends in properties in the periodic table, with elements exhibiting well-characterised homologous behaviour. This family of elements is also known as the lithium family after its leading element.

<span class="mw-page-title-main">Acid–base reaction</span> Chemical reaction between an acid and a base

In chemistry, an acid–base reaction is a chemical reaction that occurs between an acid and a base. It can be used to determine pH via titration. Several theoretical frameworks provide alternative conceptions of the reaction mechanisms and their application in solving related problems; these are called the acid–base theories, for example, Brønsted–Lowry acid–base theory.

<span class="mw-page-title-main">Carbonate</span> Salt or ester of carbonic acid

A carbonate is a salt of carbonic acid,, characterized by the presence of the carbonate ion, a polyatomic ion with the formula CO2−3. The word "carbonate" may also refer to a carbonate ester, an organic compound containing the carbonate groupO=C(−O−)2.

<span class="mw-page-title-main">Hydroxide</span> Chemical compound

Hydroxide is a diatomic anion with chemical formula OH. It consists of an oxygen and hydrogen atom held together by a single covalent bond, and carries a negative electric charge. It is an important but usually minor constituent of water. It functions as a base, a ligand, a nucleophile, and a catalyst. The hydroxide ion forms salts, some of which dissociate in aqueous solution, liberating solvated hydroxide ions. Sodium hydroxide is a multi-million-ton per annum commodity chemical. The corresponding electrically neutral compound HO is the hydroxyl radical. The corresponding covalently bound group –OH of atoms is the hydroxy group. Both the hydroxide ion and hydroxy group are nucleophiles and can act as catalysts in organic chemistry.

<span class="mw-page-title-main">Ionic bonding</span> Chemical bonding involving attraction between ions

Ionic bonding is a type of chemical bonding that involves the electrostatic attraction between oppositely charged ions, or between two atoms with sharply different electronegativities, and is the primary interaction occurring in ionic compounds. It is one of the main types of bonding, along with covalent bonding and metallic bonding. Ions are atoms with an electrostatic charge. Atoms that gain electrons make negatively charged ions. Atoms that lose electrons make positively charged ions. This transfer of electrons is known as electrovalence in contrast to covalence. In the simplest case, the cation is a metal atom and the anion is a nonmetal atom, but these ions can be more complex, e.g. molecular ions like NH+
4
or SO2−
4
. In simpler words, an ionic bond results from the transfer of electrons from a metal to a non-metal to obtain a full valence shell for both atoms.

<span class="mw-page-title-main">Salt (chemistry)</span> Chemical compound involving ionic bonding

In chemistry, a salt or ionic compound is a chemical compound consisting of an assembly of positively charged ions (cations) and negatively charged ions (anions), which results in a compound with no net electric charge. The constituent ions are held together by electrostatic forces termed ionic bonds.

<span class="mw-page-title-main">Aqueous solution</span> Solution in which the solvent is water

An aqueous solution is a solution in which the solvent is water. It is mostly shown in chemical equations by appending (aq) to the relevant chemical formula. For example, a solution of table salt, also known as sodium chloride (NaCl), in water would be represented as Na+(aq) + Cl(aq). The word aqueous means pertaining to, related to, similar to, or dissolved in, water. As water is an excellent solvent and is also naturally abundant, it is a ubiquitous solvent in chemistry. Since water is frequently used as the solvent in experiments, the word solution refers to an aqueous solution, unless the solvent is specified.

<span class="mw-page-title-main">Hydride</span> Molecule with a hydrogen bound to a more electropositive element or group

In chemistry, a hydride is formally the anion of hydrogen (H), a hydrogen ion with two electrons. In modern usage, this is typically only used for ionic bonds, but it is sometimes (and more frequently in the past) been applied to all compounds containing covalently bound H atoms. In this broad and potentially archaic sense, water (H2O) is a hydride of oxygen, ammonia is a hydride of nitrogen, etc. In covalent compounds, it implies hydrogen is attached to a less electronegative element. In such cases, the H centre has nucleophilic character, which contrasts with the protic character of acids. The hydride anion is very rarely observed.

<span class="mw-page-title-main">Acetylacetone</span> Chemical compound

Acetylacetone is an organic compound with the chemical formula CH3−C(=O)−CH2−C(=O)−CH3. It is classified as a 1,3-diketone. It exists in equilibrium with a tautomer CH3−C(=O)−CH=C(−OH)−CH3. The mixture is a colorless liquid. These tautomers interconvert so rapidly under most conditions that they are treated as a single compound in most applications. Acetylacetone is a building block for the synthesis of many coordination complexes as well as heterocyclic compounds.

<span class="mw-page-title-main">Cyanate</span> Anion with formula OCN and charge –1

The cyanate ion is an anion with the chemical formula OCN. It is a resonance of three forms: [O−C≡N] (61%) ↔ [O=C=N] (30%) ↔ [O+≡C−N2−] (4%).

<span class="mw-page-title-main">Sulfamic acid</span> Chemical compound

Sulfamic acid, also known as amidosulfonic acid, amidosulfuric acid, aminosulfonic acid, sulphamic acid and sulfamidic acid, is a molecular compound with the formula H3NSO3. This colourless, water-soluble compound finds many applications. Sulfamic acid melts at 205 °C before decomposing at higher temperatures to water, sulfur trioxide, sulfur dioxide and nitrogen.

<span class="mw-page-title-main">Potassium cyanate</span> Chemical compound

Potassium cyanate is an inorganic compound with the formula KOCN. It is a colourless solid. It is used to prepare many other compounds including useful herbicide. Worldwide production of the potassium and sodium salts was 20,000 tons in 2006.

Xenon compounds are compounds containing the element xenon (Xe). After Neil Bartlett's discovery in 1962 that xenon can form chemical compounds, a large number of xenon compounds have been discovered and described. Almost all known xenon compounds contain the electronegative atoms fluorine or oxygen. The chemistry of xenon in each oxidation state is analogous to that of the neighboring element iodine in the immediately lower oxidation state.

An alkalide is a chemical compound in which alkali metal atoms are anions with a charge or oxidation state of −1. Until the first discovery of alkalides in the 1970s, alkali metals were known to appear in salts only as cations with a charge or oxidation state of +1. These types of compounds are of theoretical interest due to their unusual stoichiometry and low ionization potentials. Alkalide compounds are chemically related to the electrides, salts in which trapped electrons are effectively the anions.

<span class="mw-page-title-main">Sodium metaborate</span> Chemical compound

Sodium metaborate is a chemical compound of sodium, boron, and oxygen with formula NaBO2. However, the metaborate ion is trimeric in the anhydrous solid, therefore a more correct formula is Na3B3O6 or (Na+)3[B3O6]3−. The formula can be written also as Na2O·B2O3 to highlight the relation to the main oxides of sodium and boron. The name is also applied to several hydrates whose formulas can be written NaBO2·nH2O for various values of n.

<span class="mw-page-title-main">Rhodizonic acid</span> Chemical compound

Rhodizonic acid is a chemical compound with formula H2C6O6 or (CO)4(COH)2. It can be seen as a twofold enol and fourfold ketone of cyclohexene, more precisely 5,6-dihydroxycyclohex-5-ene-1,2,3,4-tetrone.

Sodium cyanate is the inorganic compound with the formula NaOCN. A white solid, it is the sodium salt of the cyanate anion.

<span class="mw-page-title-main">Triuret</span> Chemical compound

Triuret is an organic compound with the formula (H2NC(O)NH)2CO. It is a product from the pyrolysis of urea. Triuret is a colorless, crystalline, hygroscopic solid, slightly soluble in cold water or ether, and more soluble in hot water. It is a planar molecule. The central carbonyl is hydrogen-bonded to both terminal amino groups.

<span class="mw-page-title-main">Monofluorophosphate</span> Chemical compound

Monofluorophosphate is an anion with the formula PO3F2−, which is a phosphate group with one oxygen atom substituted with a fluoride atom. The charge of the ion is −2. The ion resembles sulfate in size, shape and charge, and can thus form compounds with the same structure as sulfates. These include Tutton's salts and langbeinites. The most well-known compound of monofluorophosphate is sodium monofluorophosphate, commonly used in toothpaste.

<span class="mw-page-title-main">Sodium hydrogenoxalate</span> Partly deprotonated oxalic acid

Sodium hydrogenoxalate or sodium hydrogen oxalate is a chemical compound with the chemical formula NaHC2O4. It is an ionic compound. It is a sodium salt of oxalic acid H2C2O4. It is an acidic salt, because it consists of sodium cations Na+ and hydrogen oxalate anions HC2O−4 or HO−C(=O)−CO−2, in which only one acidic hydrogen atom in oxalic acid is replaced by sodium atom. The hydrogen oxalate anion can be described as the result of removing one hydrogen ion H+ from oxalic acid, or adding one to the oxalate anion C2O2−4.

References

  1. Karachinskii, S. V.; Dragalov, V. V.; Chimishkyan, A. L.; Tsvetkov, V. Yu. (1987). "Reaction of urea with alkali metal carbonates". Zhurnal Organicheskoi Khimii. 23: 93–6.  
  2. Mak, Thomas C. W.; Yip, Wai Hing; Li, Qi (1995). "Novel Hydrogen-Bonded Host Lattices Built of Urea and the Elusive Allophanate Ion". Journal of the American Chemical Society. 117 (48): 11995–11996. doi:10.1021/ja00153a022.
  3. Li, Qi; Mak, Thomas C. W. (1996). "A Novel Inclusion Compound Consolidated by Host-host and Host-guest Hydrogen Bonding: (2-hydro-xyethyl)trimethylammonium Ions Included in a Channel Host Lattice Built of Urea Molecules and Allophanate Ions". Supramolecular Chemistry. 8: 73–80. doi:10.1080/10610279608233970.