Isobutyric anhydride
{{Chembox
| Name = Isobutyric anhydride
| OtherNames = {{Unbulleted list|Isobutyric acid anhydride}}
| IUPACName = 2-Methylpropanoic anhydride
| ImageFile = Isobutyric anhydride v2.svg
| ImageSize = 150px
| Section1 = {{Chembox Identifiers
| CASNo = 97-72-3
| CASNo_Ref = {{Cascite|correct|CAS}}
| ChEBI = 84261
| ChEMBL = 1871691
| ChemSpiderID = 7069
| EC_number = 202-603-6
| UNNumber = 2924 2530
| UNII = N85A80FJDT
| InChI = 1S/C8H14O3/c1-5(2)7(9)11-8(10)6(3)4/h5-6H,1-4H3
| InChIKey = LSACYLWPPQLVSM-UHFFFAOYSA-N
| SMILES = CC(C)C(=O)OC(=O)C(C)C
| PubChem = 7346
}}
| Section2 = {{Chembox Properties
| C = 8
| H = 14
| O = 3
| MeltingPtC = -53.5
| BoilingPtC = 181.5
| Appearance = Colorless liquid{{cite web | url=https://cameochemicals.noaa.gov/chemical/940 | title=Isobutyric Anhydride | access-date=March 21, 2025}}
| Density = 0.9535 g/cm³ (at 20 °C)
| VaporPressure = 0.5 mmHg
}}
}}
Isobutyric anhydride is an organic compound with the formula {{chem2|((CH3)2CHCO)2O}}. It is an acyclic carboxylic anhydride of isobutyric acid.{{Cite web |title= Isobutyric acid anhydride (CHEBI:84261)|url=https://www.ebi.ac.uk/chebi/searchId.do?chebiId=CHEBI:84261}} It is classified as an organic acid anhydride, being derived from dehydration of isobutyric acid. It is a colorless liquid with a strong, pungent odor.{{Cite web |title=Product Description and Handling Guide - Isobutyric Anhydride |url=https://www.celanese.com/-/media/Intermediate-Chemistry/Files/Product-Descriptions/Product_Description_and_Handling_Guide-Isobutyric_Anhydride.pdf |website=Celanese |language=English }}
Isobutyric anhydride is a reagent in the production of the ester of cyclohexanone oxime.{{cite journal |doi=10.1134/s1070428008090248 |title=Preparative synthesis of cyclohexanone oxime esters |date=2008 |last1=Dikusar |first1=E. A. |last2=Zhukovskaya |first2=N. A. |journal=Russian Journal of Organic Chemistry |volume=44 |issue=9 |pages=1389–1391 }}
Applications
Isobutyric anhydride is used as an acylating agent in organic synthesis. Its primary application is in the production of esters, such as cyclohexanone oxime. Isobutyric anhydride is used in the synthesis of various dyes.{{Cite web |title= Isobutyric Anhydride | 97-72-3 | Chemical Bull PVT. LTD.|url=https://www.chemicalbull.com/products/isobutyric-anhydride}} It is also used in the production of cellulose derivatives, such as cellulose isobutyrate and cellulose acetate isobutyrate.{{Cite journal |title= Theoretical Prediction of Selectivity in Kinetic Resolution of Secondary Alcohols Catalyzed by Chiral DMAP Derivatives|date=2012 |doi=10.1021/ja302420g |url=https://pubs.acs.org/doi/10.1021/ja302420g |url-access=limited |last1=Larionov |first1=Evgeny |last2=Mahesh |first2=Mohan |last3=Spivey |first3=Alan C. |last4=Wei |first4=Yin |last5=Zipse |first5=Hendrik |journal=Journal of the American Chemical Society |volume=134 |issue=22 |pages=9390–9399 |pmid=22568686 |bibcode=2012JAChS.134.9390L |hdl=10044/1/15222 |hdl-access=free }}{{Cite journal |title= Cellulose and its derivatives: Towards biomedical applications|date=2021 |doi=10.1007/s10570-020-03674-w |last1=Seddiqi |first1=Hadi |last2=Oliaei |first2=Erfan |last3=Honarkar |first3=Hengameh |last4=Jin |first4=Jianfeng |last5=Geonzon |first5=Lester C. |last6=Bacabac |first6=Rommel G. |last7=Klein-Nulend |first7=Jenneke |journal=Cellulose |volume=28 |issue=4 |pages=1893–1931 |doi-access=free }} Another application of isobutyric anhydride is in the synthesis of various chemical derivatives. For example, it is used to produce 4-O-isobutyryl derivatives of monosaccharides.{{Cite journal |title= A Catalytic One-Step Process for the Chemo- and Regioselective Acylation of Monosaccharides|date=2007 |doi=10.1021/ja074882e |url=https://pubs.acs.org/doi/10.1021/ja074882e |url-access=limited |last1=Kawabata |first1=Takeo |last2=Muramatsu |first2=Wataru |last3=Nishio |first3=Tadashi |last4=Shibata |first4=Takeshi |last5=Schedel |first5=Hartmut |journal=Journal of the American Chemical Society |volume=129 |issue=42 |pages=12890–12895 |pmid=17902666 |bibcode=2007JAChS.12912890K }}