Product Code Database
Glyoxal is an organic compound with the chemical formula OCHCHO. It is the smallest dialdehyde (a compound with two aldehyde groups). It is a crystalline solid, white at low temperatures and yellow near the melting point (15 °C). The liquid is yellow, and the vapor is green.O'Neil, M.J. (2001): The Merck Index, 13th Edition, page 803.
Pure glyoxal is not commonly encountered because glyoxal is usually handled as a 40% aqueous solution (density near 1.24 g/mL). It forms a series of , including . For many purposes, these hydrated oligomers behave equivalently to glyoxal. Glyoxal is produced industrially as a precursor to many products.
Commercial glyoxal is prepared either by the gas-phase oxidation of ethylene glycol in the presence of a silver or copper catalyst (the Laporte process) or by the liquid-phase oxidation of acetaldehyde with nitric acid.
The first commercial glyoxal source was in Trosly-Breuil, France, started in 1960. The single largest commercial source is BASF in Ludwigshafen, Germany, at around 60,000 tons per year. Other production sites exist also in the US and China. Commercial bulk glyoxal is made and reported as a 40% solution in water by weight (approx. 1:5 molar ratio of glyoxal to water).
Anhydrous glyoxal is prepared by heating solid glyoxal hydrate(s) with phosphorus pentoxide and condensing the vapors in a cold trap.
Guanine bases in DNA can undergo non-enzymatic glycation by glyoxal to form glyoxal-guanine adducts.Vilanova B, Fernández D, Casasnovas R, Pomar AM, Alvarez-Idaboy JR, Hernández-Haro N, Grand A, Adrover M, Donoso J, Frau J, Muñoz F, Ortega-Castro J. Formation mechanism of glyoxal-DNA adduct, a DNA cross-link precursor. Int J Biol Macromol. 2017 May;98:664-675. doi: 10.1016/j.ijbiomac.2017.01.140. Epub 2017 Feb 10. PMID 28192135 These adducts may then produce DNA crosslinks. Glycation of DNA may also lead to mutation, breaks in DNA and cytotoxicity.Richarme G, Liu C, Mihoub M, Abdallah J, Leger T, Joly N, Liebart JC, Jurkunas UV, Nadal M, Bouloc P, Dairou J, Lamouri A. Guanine glycation repair by DJ-1/Park7 and its bacterial homologs. Science. 2017 Jul 14;357(6347):208-211. doi: 10.1126/science.aag1095. Epub 2017 Jun 8. PMID 28596309 In humans, glyoxal-glycated nucleotides can be repaired by the protein DJ-1 also known as Park7.
Glyoxal is used as a Solubility and agent in polymer chemistry.
Glyoxal is a valuable building block in organic synthesis, especially in the synthesis of such as . A convenient form of the reagent for use in the laboratory is its bis(hemiacetal) with ethylene glycol, 1,4-dioxane-2,3-diol. This compound is commercially available.
Glyoxal solutions can also be used as a fixative for histology, that is, a method of preserving cells for examining them under a microscope.
It is estimated that, at concentrations less than 1 M, glyoxal exists predominantly as the monomer or hydrates thereof, i.e., OCHCHO, OCHCH(OH)2, or (HO)2CHCH(OH)2. At concentrations above 1 M, dimers predominate. These dimers are probably , with the formula (HO)CH2O2CHCHO. Dimer and trimers precipitate as solids from cold solutions.
Laboratory methods
Glyoxal may be synthesized in the laboratory by oxidation of acetaldehyde with selenious acid or by ozonolysis of benzene.
Properties
The experimentally determined Henry's law constant of glyoxal is:
Biochemistry
Advanced glycation end-products (AGEs) are proteins or lipids that become Glycation as the result of a high-sugar diet. They are a bio-marker implicated in aging and the development, or worsening, of many degenerative diseases, such as diabetes, atherosclerosis, chronic kidney disease, and Alzheimer's disease.
Applications
Coated paper and textile finishes use large amounts of glyoxal as a Cross-link for starch-based formulations. It condenses with urea to afford 4,5-dihydroxy-2-imidazolidinone, which further reacts with formaldehyde to give the bis(hydroxymethyl) derivative dimethylol ethylene urea, which is used for wrinkle-resistant chemical treatments of clothing, i.e. permanent press.
Speciation in solution
Glyoxal is supplied typically as a 40% aqueous solution. Like other small , glyoxal forms hydrates. Furthermore, the hydrates condense to give a series of oligomers, some of which remain of uncertain structure. For most applications, the exact nature of the species in solution is inconsequential. At least one hydrate of glyoxal is sold commercially, glyoxal trimer dihydrate: (CHO)23(H2O)2 (CAS 4405-13-4).
Other glyoxal equivalents are available, such as the ethylene glycol hemiacetal 1,4-dioxane- trans-2,3-diol (CAS number 4845-50-5, melting point 91–95 °C).
Other occurrences
Glyoxal has been observed as a trace gas in the atmosphere, e.g. as an oxidation product of hydrocarbons. Troposphere concentrations of 0–200 ppt by volume have been reported, in polluted regions up to 1 ppb by volume.
Safety
The (oral, rats) is 3.3 g/kg, when that of common salt is 3 g/kg.
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