P-Anisic acid

p-Anisic acid ^[1]

Names
Preferred IUPAC name 4-Methoxybenzoic acid
Other names Draconic acid
Identifiers
CAS Number	100-09-4
3D model (JSmol)	Interactive image
Beilstein Reference	508910
ChEBI	CHEBI:40813
ChEMBL	ChEMBL21932 sodium salt: ChEMBL1762657
ChemSpider	10181338
ECHA InfoCard	100.002.562
EC Number	202-818-5
Gmelin Reference	3499
KEGG	C02519
PubChem CID	7478
UNII	4SB6Y7DMM3  Y
CompTox Dashboard (EPA)	DTXSID4059205
InChI InChI=1S/C8H8O3/c1-11-7-4-2-6(3-5-7)8(9)10/h2-5H,1H3,(H,9,10) Key: ZEYHEAKUIGZSGI-UHFFFAOYSA-N
SMILES O=C(O)C1=CC=C(OC)C=C1
Properties
Chemical formula	C8H8O3
Molar mass	152.149 g·mol−1
Density	1.385 g/cm3
Melting point	184 °C (363 °F; 457 K) (sublimation)
Boiling point	275 to 280 °C (527 to 536 °F; 548 to 553 K)
Solubility in water	1 part per 2500
Acidity (pKa)	4.47 [2]
Structure [3]
Crystal structure	monoclinic
Space group	P21/a
Lattice constant	a = 16.98 Å, b = 10.95 Å, c = 3.98 Å α = 90°, β = 98.7°, γ = 90°
Formula units (Z)	4
Hazards
GHS labelling: [4]
Pictograms
Signal word	Warning
Hazard statements	H302, H315, H319, H335
Precautionary statements	P261, P264, P270, P271, P280, P301+P312, P302+P352, P304+P340, P305+P351+P338, P312, P330, P332+P313, P337+P313, P362, P403+P233, P405
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

p-Anisic acid, also known as 4-methoxybenzoic acid or draconic acid, is one of the isomers of anisic acid. The term "anisic acid" often refers to this form specifically. ^[1] It is a white crystalline solid which is insoluble in water, highly soluble in alcohols, and soluble in ether and ethyl acetate. ^[1]

Synthesis and occurrence

p-Anisic acid is found naturally in anise.^{[ citation needed ]} It was first synthesized in 1841 by Auguste Cahours by oxidizing anethole that he had isolated from anise by recrystallization with diluted nitric acid: ^{[5] [6]}

CH₃CH=CHC₆H₄OCH₃ + HNO₃ → CH₃OC₆H₄CHO + others

CH₃OC₆H₄CHO + HNO₃ → CH₃OC₆H₄COOH + others

Oxidation of anisaldehyde, which was Cahours' intermediate product, is still used nowadays. ^[7] Anisic acid can also be obtained synthetically by the oxidation of p-methoxyacetophenone.

Uses

p-Anisic acid has antiseptic properties. ^[8] It is also used as an intermediate in the preparation of more complex organic compounds.

References

1. Merck Index, 11th Edition, 696
2. Braude, E. A.; Nachod, F. C., eds. (1955). Determination of Organic Structure by Physical Methods. Academic Press. ISBN   9781483275727.
3. Bryan, Robert F. (1967). "An X-ray study of the p-n-alkoxybenzoic acids. Part II. The crystal structure of anisic acid" . Journal of the Chemical Society B: Physical Organic: 1311–1316. doi:10.1039/j29670001311. ISSN   0045-6470.
4. "4-Methoxybenzoic acid". pubchem.ncbi.nlm.nih.gov. Retrieved 22 December 2021.
5. Wisniak, Jaime (2013-10-01). "Auguste André Thomas Cahours". Educación Química. 24 (4): 451–460. doi: 10.1016/S0187-893X(13)72500-X . ISSN   0187-893X.
6. Crochard (París); Arago, François; Gay-Lussac, Joseph Louis (1841). Annales de chimie et de physique (in French). Chez Crochard.
7. Saha, Rumpa; Ghosh, Aniruddha; Saha, Bidyut (2013). "Kinetics of micellar catalysis on oxidation of p-anisaldehyde to p-anisic acid in aqueous medium at room temperature". Chemical Engineering Science. 99: 23–27. Bibcode:2013ChEnS..99...23S. doi:10.1016/j.ces.2013.05.043.
8. Herman, Anna (2019). "Antimicrobial Ingredients as Preservative Booster and Components of Self-Preserving Cosmetic Products". Current Microbiology. 76 (6): 744–754. doi:10.1007/s00284-018-1492-2. PMID   29651551.