p-Toluic acid

p-Toluic acid
Names
	Preferred IUPAC name 4-Methylbenzoic acid
	Other names para-toluic acid; p-toluic acid; para-methylbenzoic acid; p-methylbenzoic acid; toluene-4-carboxylic acid; crithminic acid
Identifiers
CAS Number	99-94-5 ;
3D model (JSmol)	Interactive image;
Beilstein Reference	3904552
ChEBI	CHEBI:36635;
ChEMBL	ChEMBL21708 ;
ChemSpider	7190 ;
ECHA InfoCard	100.002.549
EC Number	202-803-3;
KEGG	C01454 ;
PubChem CID	7470;
RTECS number	XU1575000;
UNII	A26GBX5SSV ;
CompTox Dashboard (EPA)	DTXSID6021618 ;
	InChI InChI=1S/C8H8O2/c1-6-2-4-7(5-3-6)8(9)10/h2-5H,1H3,(H,9,10) Key: LPNBBFKOUUSUDB-UHFFFAOYSA-N ; InChI=1/C8H8O2/c1-6-2-4-7(5-3-6)8(9)10/h2-5H,1H3,(H,9,10) Key: LPNBBFKOUUSUDB-UHFFFAOYAB;
	SMILES O=C(O)c1ccc(cc1)C;
Properties
Chemical formula	C8H8O2
Molar mass	136.150 g·mol−1
Appearance	Crystalline solid
Density	1.06g/mL
Melting point	180 to 181 °C (356 to 358 °F; 453 to 454 K)
Boiling point	274 to 275 °C (525 to 527 °F; 547 to 548 K)
Solubility in water	Sparingly soluble in hot water
Thermochemistry
Std enthalpy of; formation (ΔfH⦵298)	-429 kJ/mol
Std enthalpy of; combustion (ΔcH⦵298)	3862 kJ/mol
Hazards
	GHS labelling:
Pictograms
Signal word	Warning
Hazard statements	H302, H315, H317, H319, H335
Precautionary statements	P261, P264, P270, P271, P272, P280, P301+P312, P302+P352, P304+P340, P305+P351+P338, P312, P321, P330, P332+P313, P333+P313, P337+P313, P362, P363, P403+P233, P405, P501
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). verify (what is ?) Infobox references

p-Toluic acid (4-methylbenzoic acid) is a substituted benzoic acid with the formula CH₃C₆H₄CO₂H. It is a white solid that is poorly soluble in water but soluble in acetone. A laboratory route to p-toluic acid involves oxidation of p-cymene with nitric acid.^[2]

Role in production of terephthalic acid

p-Toluic acid is an intermediate in the conversion of p-xylene to terephthalic acid, a commodity chemical used in the manufacture of polyethylene terephthalate. It is generated both by the oxidation of p-xylene as well as the hydrogenolysis of 4-carboxybenzaldehyde. In related processes it is converted to methyl p-toluate, which is oxidized to monomethyl terephthalate.^[3]

References

^ ^a ^b Merck Index, 12th Edition, 9673
^ W. F. Tuley; C. S. Marvel (1947). "p-Toluic Acid". Org. Synth. 27: 86. doi:10.15227/orgsyn.027.0086.
^ Tomas, Rogerio A. F.; Bordado, Joao C. M.; Gomes, Joao F. P. (2013). "p-Xylene Oxidation to Terephthalic Acid: A Literature Review Oriented toward Process Optimization and Development". Chemical Reviews. 113 (10): 7421–7469. doi:10.1021/cr300298j. PMID 23767849.

External links

Material Safety Data Sheet

[Merck-1] Merck Index, 12th Edition, 9673

[2] W. F. Tuley; C. S. Marvel (1947). "p-Toluic Acid". Org. Synth. 27: 86. doi:10.15227/orgsyn.027.0086.

[CR-3] Tomas, Rogerio A. F.; Bordado, Joao C. M.; Gomes, Joao F. P. (2013). "p-Xylene Oxidation to Terephthalic Acid: A Literature Review Oriented toward Process Optimization and Development". Chemical Reviews. 113 (10): 7421–7469. doi:10.1021/cr300298j. PMID 23767849.

[1]

[2]

[3]

Role in production of terephthalic acid

See also

References

External links