:Mucic acid
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| Verifiedfields = changed
| Watchedfields = changed
| verifiedrevid = 440609265
| ImageFile = mucic acid structure.svg
| ImageSize = 200px
| ImageAlt = Structural formula of mucic acid
| ImageFile1 = Mucic acid molecule ball.png
| ImageAlt1 = Ball-and-stick model of the mucic acid molecule
| IUPACName = meso-Galactaric acidhttps://iupac.qmul.ac.uk/2carb/23.html
| OtherNames = Galactaric acid; Galactosaccharic acid
| SystematicName = (2S,3R,4S,5R)-2,3,4,5-Tetrahydroxyhexanedioic acid
| Section1 = {{Chembox Identifiers
| CASNo_Ref = {{cascite|correct|??}}
| CASNo=526-99-8
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = E149J5OTIF
| PubChem=3037582
| ChEMBL_Ref = {{ebicite|changed|EBI}}
| ChEMBL = 1232958
| ChemSpiderID_Ref = {{chemspidercite|changed|chemspider}}
| ChemSpiderID = 2301286
| SMILES = [C@@H]([C@@H]([C@H](C(=O)O)O)O)([C@@H](C(=O)O)O)O
| InChI = 1/C6H10O8/c7-1(3(9)5(11)12)2(8)4(10)6(13)14/h1-4,7-10H,(H,11,12)(H,13,14)/t1-,2+,3+,4-
| InChIKey = DSLZVSRJTYRBFB-DUHBMQHGBT
| StdInChI_Ref = {{stdinchicite|changed|chemspider}}
| StdInChI = 1S/C6H10O8/c7-1(3(9)5(11)12)2(8)4(10)6(13)14/h1-4,7-10H,(H,11,12)(H,13,14)/t1-,2+,3+,4-
| StdInChIKey_Ref = {{stdinchicite|changed|chemspider}}
| StdInChIKey = DSLZVSRJTYRBFB-DUHBMQHGSA-N
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| Section2 = {{Chembox Properties
| C=6 | H=10 | O=8
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| Density=
| MeltingPtC=230
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| Section3 = {{Chembox Hazards
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Mucic acid, C6H10O8 or HOOC-(CHOH)4-COOH (galactaric acid or meso-galactaric acid) is an aldaric acid obtained by nitric acid oxidation of galactose or galactose-containing compounds such as lactose, dulcite, quercite, and most varieties of gum.{{cite EB1911 |wstitle=Mucic Acid |volume=18 |page=954}}
Properties
Mucic acid forms a crystalline powder, which melts at 210–230 °C.{{cite web |url=http://www.chemspider.com/Chemical-Structure.2301286.html |title=Mucic acid |work=ChemSpider |accessdate=30 March 2018}} It is insoluble in alcohol, and nearly insoluble in cold water. Due to the symmetry in the molecule, it is optically inactive even though it has chiral carbon atoms (i.e., it is a meso compound).
Reactions
When heated with pyridine to 140 °C, it is converted into allomucic acid.{{Cite journal | doi = 10.1021/ja01382a029| title = The Preparation of Allomucic Acid and Certain of Its Derivatives| journal = Journal of the American Chemical Society| volume = 51| issue = 7| pages = 2167| year = 1929| last1 = Butler | first1 = C. L.| last2 = Cretcher | first2 = L. H. }} When digested with fuming hydrochloric acid for some time it is converted into αα′ furfural dicarboxylic acid while on heating with barium sulfide it is transformed into α-thiophene carboxylic acid. The ammonium salt yields on dry distillation carbon dioxide, ammonia, pyrrol and other substances. The acid when fused with caustic alkalis yields oxalic acid.
With potassium bisulfate mucic acid forms 3-hydroxy-2-pyrone by dehydration and decarboxylation.
:File:3-hydroxy-2-pyrone.svg 160 °C / 4 hrs. b) hydrochloric acid to pH = 7]]{{clear|left}}
Use
Mucic acid can be used to replace tartaric acid in self-raising flour or fizzies.
It has been used as a precursor of adipic acid in the way to nylon by a rhenium-catalyzed deoxydehydration reaction.{{Cite journal | doi = 10.1002/anie.201310991| title = Highly Efficient Chemical Process to Convert Mucic Acid into Adipic Acid and DFT Studies of the Mechanism of the Rhenium-Catalyzed Deoxydehydration| journal = Angewandte Chemie International Edition| volume = 53| issue = 16| pages = 4200–4204| year = 2014| last1 = Li | first1 = X. | last2 = Wu | first2 = D. | last3 = Lu | first3 = T. | last4 = Yi | first4 = G. | last5 = Su | first5 = H. | last6 = Zhang | first6 = Y. | pmid=24623498}}
It has been used as a precursor of Taxol in Nicolaou Taxol total synthesis (1994).