Phenylglyoxylic acid

Phenylglyoxylic acid is the organic compound with the formula C₆H₅C(O)CO₂H. The conjugate base, known as benzoylformate, is the substrate of benzoylformate decarboxylase, a thiamine diphosphate-dependent enzyme:

benzoylformate + H⁺ ⇌ benzaldehyde + CO₂

Phenylglyoxylic acid

Names
Preferred IUPAC name Oxo(phenyl)acetic acid
Other names Benzoyl formate Phenylglyoxalic acid Phenylglyoxylate
Identifiers
CAS Number	611-73-4 Y
3D model (JSmol)	Interactive image
ChEBI	CHEBI:18280 N
ChemSpider	11421 N
ECHA InfoCard	100.009.345
EC Number	210-278-7
KEGG	C02137 N
PubChem CID	11915
UNII	2PZL5A0W0M Y
CompTox Dashboard (EPA)	DTXSID80209993
InChI InChI=1S/C8H6O3/c9-7(8(10)11)6-4-2-1-3-5-6/h1-5H,(H,10,11) N Key: FAQJJMHZNSSFSM-UHFFFAOYSA-N N InChI=1/C8H6O3/c9-7(8(10)11)6-4-2-1-3-5-6/h1-5H,(H,10,11) Key: FAQJJMHZNSSFSM-UHFFFAOYAS
SMILES C1=CC=C(C=C1)C(=O)C(=O)O
Properties
Chemical formula	C8H6O3
Molar mass	150.13 g/mol
Appearance	colorless solid
Melting point	64 to 66 °C (147 to 151 °F; 337 to 339 K)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). N verify (what is YN ?) Infobox references

It is a colourless solid with a melting point of 64–66 °C and is moderately acidic (pK_a = 2.15).

Phenylglyoxylic acid can be synthesized by oxidation of mandelic acid with potassium permanganate.^[1] An alternative synthesis involves hydrolysis of benzoyl cyanide.^[2]