WordNet

a compound formed from one or more other compounds in a reaction resulting in removal of water
organic compounds that react with water to form an acid (同)acid_anhydrides

PrepTutorEJDIC

無水化合物,酸無水物

Wikipedia preview

出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2013/03/16 21:18:21」(JST)

wiki en

[Wiki en表示]

"Anhydride" redirects here. For inorganic acid anhydrides, see acidic oxide.

Generic example of an acid anhydride.

An acid anhydride is an organic compound that has two acyl groups bound to the same oxygen atom.^[1] Most commonly, the acyl groups are derived from the same carboxylic acid, the formula of the anhydride being (RC(O))₂O. Symmetrical acid anhydrides of this type are named by replacing the word acid in the name of the parent carboxylic acid by the word anhydride.^[2] Thus, (CH₃CO)₂O is called acetic anhydride. Mixed (or unsymmetrical) acid anhydrides, such as acetic formic anhydride (see below), are known.

Important acid anhydrides

Acetic anhydride is a major industrial chemical widely used for preparing acetate esters, e.g. cellulose acetate. Maleic anhydride is the precursor to various resins by copolymerization with styrene. Maleic anhydride is a dienophile in the Diels-Alder reaction.^[3]

Anhydrides not derived from carboxylic acids only

Anhydrides derived from other organic acids

One or both acyl groups of an acid anhydride may also be derived from another type of organic acid, such as sulfonic acid or a phosphonic acid.

Anhydrides that include an inorganic acid

One of the acyl groups of an acid anhydride can be derived from an inorganic acid such as phosphoric acid. The mixed anhydride 1,3-bisphosphoglycerate, which is an intermediate in the formation of ATP via glycolysis,^[4] is the mixed anhydride between 3-phosphoglyceric acid and phosphoric acid.

Preparation

Acid anhydrides are prepared in industry by diverse means. Acetic anhydride is mainly produced by the carbonylation of methyl acetate.^[5] Maleic anhydride is produced by the oxidation of benzene or butane. Laboratory routes emphasize the dehydration of the corresponding acids. The conditions vary from acid to acid, but phosphorus pentoxide is a common dehydrating agent:

2 CH₃COOH + P₄O₁₀ → CH₃C(O)OC(O)CH₃ + "(HO)₂P₄O₉"

Acid chlorides are also effective precursors:^[6]

CH₃C(O)Cl + HCO₂Na → HCO₂COCH₃ + NaCl

Mixed anhydrides containing the acetyl group are prepared from ketene:

RCO₂H + H₂C=C=O → RCO₂C(O)CH₃

Reactions

Acid anhydrides are a source of reactive acyl groups, and their reactions and uses resemble those of acyl halides. In reactions with protic substrates, the reactions afford equal amounts of the acylated product and the carboxylic acid:

RC(O)OC(O)R + HY → RC(O)Y + RCO₂H

for HY = HOR (alcohols), HNR'₂ (ammonia, primary, secondary amines), aromatic ring (see Friedel-Crafts acylation).

Acid anhydrides tend to be less electrophilic than acyl chlorides, and only one acyl group is transferred per molecule of acid anhydride, which leads to a lower atom efficiency. The low cost, however, of acetic anhydride makes it a common choice for acetylation reactions.

Sulfur analogues

Sulfur can replace oxygen, either in the carbonyl group or in the bridge. In the former case, the name of the acyl group is enclosed in parentheses to avoid ambiguity in the name,^[2] e.g., (thioacetic) anhydride (CH₃C(S)OC(S)CH₃). When two acyl groups are attached to the same sulfur atom, the resulting compound is called a thioanhydride,^[2] e.g., acetic thioanhydride ((CH₃C(O))₂S).

Dianhydrides

Dianhydrides are molecules containing two acid anhydride functions. They are mainly used to synthesize polyimides and sometimes polyesters and polyamides.

Examples of dianhydrides: pyromellitic dianhydride (PMDA), 3,3’, 4,4’ - oxydiphtalic dianhydride (ODPA), 3,3’, 4,4’-benzophenone tetracarboxylic dianhydride (BTDA), 4,4’-diphtalic (hexafluoroisopropylidene) anhydride (6FDA), benzoquinonetetracarboxylic dianhydride, ethylenetetracarboxylic dianhydride.

Polyanhydrides

Main article: Polyanhydrides

Polyanhydrides are a class of polymers characterized by anhydride bonds that connect repeat units of the polymer backbone chain.

References

^ Nic, M.; Jirat, J.; Kosata, B., eds. (2006–). "acid anhydrides". IUPAC Compendium of Chemical Terminology (Online ed.). doi:10.1351/goldbook.{{{file}}}. ISBN 0-9678550-9-8. http://goldbook.iupac.org/A00072.html.
^ ^a ^b ^c Panico, R.; Powell, W. H.; Richer, J. C., eds. (1993). "Recommendation R-5.7.7". A Guide to IUPAC Nomenclature of Organic Compounds. IUPAC/Blackwell Science. pp. 123–25. ISBN 0-632-03488-2. http://www.acdlabs.com/iupac/nomenclature/.
^ Heimo Held, Alfred Rengstl, Dieter Mayer "Acetic Anhydride and Mixed Fatty Acid Anhydrides" Ullmann's Encyclopedia of Industrial Chemistry 2002, Wiley-VCH, Weinheim. doi:10.1002/14356007.a01_065
^ Nelson, D. L.; Cox, M. M. "Lehninger, Principles of Biochemistry" 3rd Ed. Worth Publishing: New York, 2000. ISBN 1-57259-153-6.
^ Zoeller, J. R.; Agreda, V. H.; Cook, S. L.; Lafferty, N. L.; Polichnowski, S. W.; Pond, D. M. "Eastman Chemical Company Acetic Anhydride Process" Catalysis Today (1992), volume 13, pp.73-91. doi:10.1016/0920-5861(92)80188-S
^ Lewis I. Krimen (1988), "Acetic Formic Anhydride", Org. Synth., http://www.orgsyn.org/orgsyn/orgsyn/prepContent.asp?prep=CV6P0008; Coll. Vol. 6: 8

http://www.chemguide.co.uk/organicprops/anhydrides/background.html

UpToDate Contents

全文を閲覧するには購読必要です。 To read the full text you will need to subscribe.

1. 職業性喘息：定義、疫学、原因、および危険因子 occupational asthma definitions epidemiology causes and risk factors
2. 職業性喘息：病因 occupational asthma pathogenesis
3. 職業性喘息：管理、予後と予防 occupational asthma management prognosis and prevention
4. びまん性肺胞出血症候群 the diffuse alveolar hemorrhage syndromes
5. 大量喀血の概要 overview of massive hemoptysis

English Journal

PMID 26706556

The Activation of Free Dipeptides Promoted by Strong Activating Agents in Water Does not Yield Diketopiperazines.

Beaufils D1, Jepaul S1, Liu Z1, Boiteau L1, Pascal R2.
Origins of life and evolution of the biosphere : the journal of the International Society for the Study of the Origin of Life.Orig Life Evol Biosph.2016 Mar;46(1):19-30. doi: 10.1007/s11084-015-9455-0. Epub 2015 Jul 24.
The activation of dipeptides was studied in the perspective of the abiotic formation of oligopeptides of significant length as a requirement for secondary structure formation. The formation of piperazin-2,5-diones (DKP), previously considered as a dead end when activating free dipeptides, was shown
PMID 26205652

Synthesis of photo-crosslinkable hyaluronan with tailored degree of substitution suitable for production of water resistant nanofibers.

Huerta-Angeles G1, Brandejsová M2, Knotková K2, Hermannová M2, Moravcová M2, Šmejkalová D2, Velebný V2.
Carbohydrate polymers.Carbohydr Polym.2016 Feb 10;137:255-63. doi: 10.1016/j.carbpol.2015.10.077. Epub 2015 Nov 2.
In this work, hyaluronan (HA) was grafted by a novel and an efficient mixed anhydrides methodology with (hetero)-aryl and aliphatic acrylic moieties suitable for cross-linking. A precise control of stoichiometry was achieved. Derivatives with degree of substitution (DS) below 20% did not show self-c
PMID 26686128