Phthalaldehyde

Phthalaldehyde
Names
	IUPAC name Phthalaldehyde
	Preferred IUPAC name Benzene-1,2-dicarbaldehyde
	Other names Benzene-1,2-dicarboxaldehyde; o-Phthalaldehyde; o-Phthalic dicarboxaldehyde; Phthaldialdehyde
Identifiers
CAS Number	643-79-8 ;
3D model (JSmol)	Interactive image;
ChEBI	CHEBI:70851 ;
ChemSpider	4642 ;
ECHA InfoCard	100.010.367
EC Number	211-402-2;
PubChem CID	4807;
RTECS number	TH6950000;
UNII	4P8QP9768A ;
UN number	2923
CompTox Dashboard (EPA)	DTXSID6032514 ;
	InChI InChI=1S/C8H6O2/c9-5-7-3-1-2-4-8(7)6-10/h1-6H;
	SMILES O=Cc1ccccc1C=O;
Properties
Chemical formula	C8H6O2
Molar mass	134.134 g·mol−1
Appearance	Yellow solid
Density	1.19 g/mL
Melting point	55.5–56 °C (131.9–132.8 °F; 328.6–329.1 K)
Boiling point	266.1 °C (511.0 °F; 539.2 K)
Solubility in water	Low
Hazards
	Occupational safety and health (OHS/OSH):
Main hazards	Toxic, Irritant
	GHS labelling:
Pictograms
Signal word	Danger
Hazard statements	H228, H301, H314, H315, H317, H335, H373, H410
Precautionary statements	P210, P240, P241, P260, P261, P264, P270, P271, P272, P273, P280, P301+P310, P301+P330+P331, P302+P352, P303+P361+P353, P304+P340, P305+P351+P338, P310, P312, P314, P321, P330, P332+P313, P333+P313, P362, P363, P370+P378, P391, P403+P233, P405, P501
Flash point	132 °C (270 °F; 405 K)
	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

Phthalaldehyde (sometimes also o-phthalaldehyde or ortho-phthalaldehyde, OPA) is the chemical compound with the formula C₆H₄(CHO)₂. It is one of three isomers of benzene dicarbaldehyde, related to phthalic acid. This pale yellow solid is a building block in the synthesis of heterocyclic compounds and a reagent in the analysis of amino acids. OPA dissolves in water solution at pH < 11.5. Its solutions degrade upon UV illumination and exposure to air.