Glycolic acid

Last updated
Glycolic acid
Chemical structure of glycolic acid Glycolic acid.svg
Chemical structure of glycolic acid
Ball-and-stick model of glycolic acid Glycolic acid3d.png
Ball-and-stick model of glycolic acid
Glycolic Acid.jpg
Names
Preferred IUPAC name
Hydroxyacetic acid
Other names
Hydroacetic acid
2-Hydroxyethanoic acid
Identifiers
3D model (JSmol)
ChEBI
ChEMBL
ChemSpider
DrugBank
ECHA InfoCard 100.001.073 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 201-180-5
KEGG
PubChem CID
RTECS number
  • MC5250000
UNII
  • InChI=1S/C2H4O3/c3-1-2(4)5/h3H,1H2,(H,4,5) Yes check.svgY
    Key: AEMRFAOFKBGASW-UHFFFAOYSA-N Yes check.svgY
  • InChI=1/C2H4O3/c3-1-2(4)5/h3H,1H2,(H,4,5)
    Key: AEMRFAOFKBGASW-UHFFFAOYAR
  • OC(=O)CO
Properties
C2H4O3
Molar mass 76.05 g/mol
AppearanceWhite powder or colorless crystals
Density 1.49 g/cm3 [1]
Melting point 75 °C (167 °F; 348 K)
Boiling point 100 °C (212 °F; 373 K) Decomposes above 100 °C
70% solution
Solubility in other solvents Alcohols, acetone,
acetic acid and
ethyl acetate [2]
log P −1.05 [3]
Vapor pressure 1.051 kPa (80 °C)
Acidity (pKa)3.83
Hazards
Occupational safety and health (OHS/OSH):
Main hazards
Corrosive
GHS labelling:
GHS-pictogram-acid.svg GHS-pictogram-exclam.svg
Danger
H302, H314, H332
P260, P261, P264, P270, P271, P280, P301+P312, P301+P330+P331, P303+P361+P353, P304+P312, P304+P340, P305+P351+P338, P310, P312, P321, P330, P363, P405, P501
NFPA 704 (fire diamond)
NFPA 704.svgHealth 3: Short exposure could cause serious temporary or residual injury. E.g. chlorine gasFlammability 1: Must be pre-heated before ignition can occur. Flash point over 93 °C (200 °F). E.g. canola oilInstability 1: Normally stable, but can become unstable at elevated temperatures and pressures. E.g. calciumSpecial hazards (white): no code
3
1
1
Flash point 300 °C (572 °F; 573 K) [4]
Lethal dose or concentration (LD, LC):
1950 mg/kg (rat, oral)
2040 mg/kg (rat, oral)
7.7 ppm (rat, 4h)
3.6 ppm (rat, 4h)
Related compounds
Lactic acid
Related compounds
Glycolaldehyde
Acetic acid
Glycerol
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
X mark.svgN  verify  (what is  Yes check.svgYX mark.svgN ?)

Glycolic acid (or hydroxyacetic acid; chemical formula HOCH2CO2H) is a colorless, odorless and hygroscopic crystalline solid, highly soluble in water. It is used in various skin-care products. Glycolic acid is widespread in nature. A glycolate (sometimes spelled "glycollate") is a salt or ester of glycolic acid.

Contents

History

The name "glycolic acid" was coined in 1848 by French chemist Auguste Laurent (1807–1853). He proposed that the amino acid glycine—which was then called glycocolle—might be the amine of a hypothetical acid, which he called "glycolic acid" (acide glycolique). [5]

Glycolic acid was first prepared in 1851 by German chemist Adolph Strecker (1822–1871) and Russian chemist Nikolai Nikolaevich Sokolov (1826–1877). They produced it by treating hippuric acid with nitric acid and nitrogen dioxide to form an ester of benzoic acid and glycolic acid (C6H5C(=O)OCH2COOH), which they called "benzoglycolic acid" (Benzoglykolsäure; also benzoyl glycolic acid). They boiled the ester for days with dilute sulfuric acid, thereby obtaining benzoic acid and glycolic acid (Glykolsäure). [6] [7]

Preparation

Glycolic acid can be synthesized in various ways. The predominant approaches use a catalyzed reaction of formaldehyde with synthesis gas (carbonylation of formaldehyde), for its low cost. [8]

It is also prepared by the reaction of chloroacetic acid with sodium hydroxide followed by re-acidification.

Other methods, not noticeably in use, include hydrogenation of oxalic acid, and hydrolysis of the cyanohydrin derived from formaldehyde. [9] Some of today's glycolic acids are formic acid-free. Glycolic acid can be isolated from natural sources, such as sugarcane, sugar beets, pineapple, cantaloupe and unripe grapes. [10]

Glycolic acid can also be prepared using an enzymatic biochemical process that may require less energy. [11]

Properties

Glycolic acid is slightly stronger than acetic acid due to the electron-withdrawing power of the terminal hydroxyl group. The carboxylate group can coordinate to metal ions, forming coordination complexes. Of particular note are the complexes with Pb2+ and Cu2+ which are significantly stronger than complexes with other carboxylic acids. This indicates that the hydroxyl group is involved in complex formation, possibly with the loss of its proton. [12]

Applications

Glycolic acid is used in the textile industry as a dyeing and tanning agent. [13]

Organic synthesis

Glycolic acid is a useful intermediate for organic synthesis, in a range of reactions including: oxidation-reduction, esterification and long chain polymerization. It is used as a monomer in the preparation of polyglycolic acid and other biocompatible copolymers (e.g. PLGA). Commercially, important derivatives include the methyl (CAS# 96-35-5) and ethyl (CAS# 623-50-7) esters which are readily distillable (boiling points 147–149 °C and 158–159 °C, respectively), unlike the parent acid. The butyl ester (b.p. 178–186 °C) is a component of some varnishes, being desirable because it is nonvolatile and has good dissolving properties. [9]

Occurrence

Plants produce glycolic acid during photorespiration. It is recycled by conversion to glycine within the peroxisomes and to tartronic acid semialdehyde within the chloroplasts. [14]

Because photorespiration is a wasteful side reaction in regard to photosynthesis, much effort has been devoted to suppressing its formation. One process converts glycolate into glycerate without using the conventional BASS6 and PLGG1 route; see glycerate pathway. [15] [16]

Safety

Glycolic acid is an irritant to the skin. [17] It occurs in all green plants. [9]

Related Research Articles

<span class="mw-page-title-main">Benzoic acid</span> Organic compound (C6H5COOH)

Benzoic acid is a white solid organic compound with the formula C6H5COOH, whose structure consists of a benzene ring with a carboxyl substituent. The benzoyl group is often abbreviated "Bz", thus benzoic acid is also denoted as BzOH, since the benzoyl group has the formula –C6H5CO. It is the simplest aromatic carboxylic acid. The name is derived from gum benzoin, which was for a long time its only source.

<span class="mw-page-title-main">Glycine</span> Amino acid

Glycine (symbol Gly or G; ) is an amino acid that has a single hydrogen atom as its side chain. It is the simplest stable amino acid (carbamic acid is unstable). In the gas phase, it is a molecule with the chemical formula NH2CH2‐COOH. In solution or in the solid, glycine exists as the zwitterion. Glycine is one of the proteinogenic amino acids. It is encoded by all the codons starting with GG (GGU, GGC, GGA, GGG). Glycine is integral to the formation of alpha-helices in secondary protein structure due to the "flexibility" caused by such a small R group. Glycine is also an inhibitory neurotransmitter – interference with its release within the spinal cord (such as during a Clostridium tetani infection) can cause spastic paralysis due to uninhibited muscle contraction.

<span class="mw-page-title-main">Photorespiration</span> Process in plant metabolism

Photorespiration (also known as the oxidative photosynthetic carbon cycle or C2 cycle) refers to a process in plant metabolism where the enzyme RuBisCO oxygenates RuBP, wasting some of the energy produced by photosynthesis. The desired reaction is the addition of carbon dioxide to RuBP (carboxylation), a key step in the Calvin–Benson cycle, but approximately 25% of reactions by RuBisCO instead add oxygen to RuBP (oxygenation), creating a product that cannot be used within the Calvin–Benson cycle. This process lowers the efficiency of photosynthesis, potentially lowering photosynthetic output by 25% in C3 plants. Photorespiration involves a complex network of enzyme reactions that exchange metabolites between chloroplasts, leaf peroxisomes and mitochondria.

<span class="mw-page-title-main">Benzyl alcohol</span> Aromatic alcohol

Benzyl alcohol (also known as α-cresol) is an aromatic alcohol with the formula C6H5CH2OH. The benzyl group is often abbreviated "Bn" (not to be confused with "Bz" which is used for benzoyl), thus benzyl alcohol is denoted as BnOH. Benzyl alcohol is a colorless liquid with a mild pleasant aromatic odor. It is a useful as a solvent for its polarity, low toxicity, and low vapor pressure. Benzyl alcohol has moderate solubility in water (4 g/100 mL) and is miscible in alcohols and diethyl ether. The anion produced by deprotonation of the alcohol group is known as benzylate or benzyloxide.

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

Sodium benzoate also known as benzoate of soda is the sodium salt of benzoic acid, widely used as a food preservative (with an E number of E211) and a pickling agent. It appears as a white crystalline chemical with the formula C6H5COONa.

<span class="mw-page-title-main">Calvin cycle</span> Light-independent reactions in photosynthesis

The Calvin cycle, light-independent reactions, bio synthetic phase, dark reactions, or photosynthetic carbon reduction (PCR) cycle of photosynthesis is a series of chemical reactions that convert carbon dioxide and hydrogen-carrier compounds into glucose. The Calvin cycle is present in all photosynthetic eukaryotes and also many photosynthetic bacteria. In plants, these reactions occur in the stroma, the fluid-filled region of a chloroplast outside the thylakoid membranes. These reactions take the products of light-dependent reactions and perform further chemical processes on them. The Calvin cycle uses the chemical energy of ATP and reducing power of NADPH from the light dependent reactions to produce sugars for the plant to use. These substrates are used in a series of reduction-oxidation (redox) reactions to produce sugars in a step-wise process; there is no direct reaction that converts several molecules of CO2 to a sugar. There are three phases to the light-independent reactions, collectively called the Calvin cycle: carboxylation, reduction reactions, and ribulose 1,5-bisphosphate (RuBP) regeneration.

Drug metabolism is the metabolic breakdown of drugs by living organisms, usually through specialized enzymatic systems. More generally, xenobiotic metabolism is the set of metabolic pathways that modify the chemical structure of xenobiotics, which are compounds foreign to an organism's normal biochemistry, such as any drug or poison. These pathways are a form of biotransformation present in all major groups of organisms and are considered to be of ancient origin. These reactions often act to detoxify poisonous compounds. The study of drug metabolism is called pharmacokinetics.

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

Polyglycolide or poly(glycolic acid) (PGA), also spelled as polyglycolic acid, is a biodegradable, thermoplastic polymer and the simplest linear, aliphatic polyester. It can be prepared starting from glycolic acid by means of polycondensation or ring-opening polymerization. PGA has been known since 1954 as a tough fiber-forming polymer. Owing to its hydrolytic instability, however, its use has initially been limited. Currently polyglycolide and its copolymers (poly(lactic-co-glycolic acid) with lactic acid, poly(glycolide-co-caprolactone) with ε-caprolactone and poly (glycolide-co-trimethylene carbonate) with trimethylene carbonate) are widely used as a material for the synthesis of absorbable sutures and are being evaluated in the biomedical field.

The Cannizzaro reaction, named after its discoverer Stanislao Cannizzaro, is a chemical reaction which involves the base-induced disproportionation of two molecules of a non-enolizable aldehyde to give a primary alcohol and a carboxylic acid.

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

Hippuric acid is a carboxylic acid and organic compound. It is found in urine and is formed from the combination of benzoic acid and glycine. Levels of hippuric acid rise with the consumption of phenolic compounds. The phenols are first converted to benzoic acid, and then to hippuric acid and excreted in urine.

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

Phenylacetone, also known as phenyl-2-propanone, is an organic compound with the chemical formula C6H5CH2COCH3. It is a colorless oil that is soluble in organic solvents. It is a mono-substituted benzene derivative, consisting of an acetone attached to a phenyl group. As such, its systematic IUPAC name is 1-phenyl-2-propanone.

<span class="mw-page-title-main">Ellagic acid</span> Natural phenol antioxidant

Ellagic acid is a polyphenol found in numerous fruits and vegetables. It is the dilactone of hexahydroxydiphenic acid.

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

Glyoxylic acid or oxoacetic acid is an organic compound. Together with acetic acid, glycolic acid, and oxalic acid, glyoxylic acid is one of the C2 carboxylic acids. It is a colourless solid that occurs naturally and is useful industrially.

Toluene toxicity refers to the harmful effects caused by toluene on the body.

Alpha hydroxy carboxylic acids, or α-hydroxy carboxylic acids (AHAs), are a group of carboxylic acids featuring a hydroxy group located one carbon atom away from the acid group. This structural aspect distinguishes them from beta hydroxy acids, where the functional groups are separated by two carbon atoms. Notable AHAs include glycolic acid, lactic acid, mandelic acid, and citric acid.

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

Rongalite is a chemical compound with the molecular formula Na+HOCH2SO2. This salt has many additional names, including Rongalit, sodium hydroxymethylsulfinate, sodium formaldehyde sulfoxylate, and Bruggolite. It is listed in the European Cosmetics Directive as sodium oxymethylene sulfoxylate (INCI). It is water-soluble and generally sold as the dihydrate. The compound and its derivatives are widely used in the dye industry. The structure of this salt has been confirmed by X-ray crystallography.

<span class="mw-page-title-main">Erlenmeyer–Plöchl azlactone and amino-acid synthesis</span>

The Erlenmeyer–Plöchl azlactone and amino acid synthesis, named after Friedrich Gustav Carl Emil Erlenmeyer who partly discovered the reaction, is a series of chemical reactions which transform an N-acyl glycine to various other amino acids via an oxazolone.

<span class="mw-page-title-main">Adolph Strecker</span> German chemist (1822-1871)

Adolph Strecker was a German chemist who is remembered primarily for his work with amino acids.

<span class="mw-page-title-main">Glycerate dehydrogenase</span>

In enzymology, a glycerate dehydrogenase (EC 1.1.1.29) is an enzyme that catalyzes the chemical reaction

<span class="mw-page-title-main">Hydroxyacid oxidase (glycolate oxidase) 1</span> Protein-coding gene in the species Homo sapiens

Hydroxyacid oxidase 1 is a protein that in humans is encoded by the HAO1 gene.

References

  1. United States National Library of Medicine "Hydroxyacetic Acid" in TOXNET Hazardous Substances Data Bank (HSDB), citing Gerhartz, W. (exec ed.), Ullmann's Encyclopedia of Industrial Chemistry. 5th ed.Vol A1: Deerfield Beach, FL: VCH Publishers, 1985 to Present., p. VA13 509.
  2. "DuPont Glycolic Acid Technical Information". Archived from the original on 2006-07-14. Retrieved 2006-07-06.
  3. "Glycolic acid". www.chemsrc.com. Archived from the original on 2020-07-27. Retrieved 2018-05-16.
  4. "Glycolic Acid MSDS". University of Akron. Retrieved 2006-09-18.[ permanent dead link ]
  5. Laurent, Auguste (1848). "Sur les acides amidés et le sucre de gélatine" Archived 2020-07-27 at the Wayback Machine ("On aminated acids and the sugar of gelatine [i.e., glycine]"), Annales de Chimie et de Physique, 3rd series, 23: 110–123. From p. 112: "Appelons ce dernier acide glycolique ... " ("Let us call the latter 'glycolic acid' ...")
  6. Socoloff, Nicolaus and Strecker, Adolph (1851) "Untersuchung einiger aus der Hippursäure entstehenden Producte" Archived 2020-07-27 at the Wayback Machine ("Investigation of some products that arise from hippuric acid"), Annalen der Chemie und Pharmacie, 80: 17–43. For their production of glycolic acid, see pp. 34–37. Note: Strecker and Sokolov's empirical formula for glycolic acid (viz, C4H4O6) was incorrect, because like many chemists at that time, they used the wrong atomic masses for carbon (6 instead of 12) and for oxygen (8 instead of 16).
  7. (Socoloff and Strecker, 1851), p. 37. In recognition of Laurent's correct surmise, Strecker and Sokolov named glycolic acid: "Die in dem Barytsalz enthaltene Säure C4H3O5 oder als Säurehydrat gedacht C4H4O6 kommt mit der Säure überein, als deren Amidverbindung man das Glycocoll betrachten kann, und welche daher von Laurent den Namen Glycolsäure erhalten hat." (The acid C4H3O5 contained in the barium salt — or considered as the acid hydrate C4H4O6 — is consistent with the acid whose amide can be regarded as glycocoll and which therefore obtained from Laurent the name "glycolic acid".)
  8. D.J. Loder, U.S. patent 2,152,852 (1939).
  9. 1 2 3 Karlheinz Miltenberger (2005). "Hydroxycarboxylic Acids, Aliphatic". Ullmann's Encyclopedia of Industrial Chemistry . Weinheim: Wiley-VCH. doi:10.1002/14356007.a13_507. ISBN   978-3527306732.
  10. "Glycolic acid, What is Glycolic acid? About its Science, Chemistry and Structure". www.3dchem.com. Archived from the original on 2018-04-12. Retrieved 2018-04-11.
  11. "Glycolic acid". thaipolychemicals.weebly.com. Archived from the original on 2017-08-25. Retrieved 2017-05-02.
  12. Sigel, Astrid; Operschall, Bert P.; Sigel, Helmut (2017). "Chapter 11. Complex Formation of Lead(II) with Nucleotides and Their Constituents". In Astrid, S.; Helmut, S.; Sigel, R. K. O. (eds.). Lead: Its Effects on Environment and Health. Metal Ions in Life Sciences. Vol. 17. de Gruyter. pp. 319–402. doi:10.1515/9783110434330-011. PMID   28731304.
  13. "DuPont Glycolic Acid Leather Dyeing & Tanning Applications". Archived from the original on 2013-05-22. Retrieved 2013-04-11.
  14. Kisaki, T.; Tolbert, N. E. "Glycolate and glyoxylate metabolism by isolated peroxisomes or chloroplasts". Plant Physiology. pp. 242–250. doi:10.1104/pp.44.2.242. PMC   396069 . PMID   16657053 . Retrieved 2023-08-24.
  15. Gerea, Alexandra (2017-04-03). "New protein can increase yields, save farmers millions every year". ZME Science. Archived from the original on 2017-04-07. Retrieved 2017-04-06.
  16. South, Paul F.; Walker, Berkley J.; Cavanagh, Amanda P.; Rolland, Vivien; Badger, Murray; Ort, Donald R. (2017-03-28). "Bile Acid Sodium Symporter BASS6 Can Transport Glycolate and Is Involved in Photorespiratory Metabolism in Arabidopsis thaliana". The Plant Cell. 29 (4): 808–823. doi:10.1105/tpc.16.00775. ISSN   1532-298X. PMC   5435425 . PMID   28351992.
  17. "Glycolic Acid MSDS". ICSC:NENG1537 International Chemical Safety Cards (WHO/IPCS/ILO). CDC/NIOSH. Archived from the original on 2005-09-21. Retrieved 2006-06-08.