Bis ,4,5-trichloro-6-(pentyloxycarbonyl)phenylxalate (also known as bis(2,4,5-trichloro-6-carbopentoxyphenyl) oxalate or CPPO) is an

organic compound Some chemical authorities define an organic compound as a chemical compound that contains a carbon–hydrogen or carbon–carbon bond; others consider an organic compound to be any chemical compound that contains carbon. For example, carbon-co ...

with the formula . A white solid, it is classified as a diester of

oxalic acid Oxalic acid is an organic acid with the systematic name ethanedioic acid and chemical formula , also written as or or . It is the simplest dicarboxylic acid. It is a white crystalline solid that forms a colorless solution in water. Its name i ...

. It is an active ingredient for the

chemiluminescence Chemiluminescence (also chemoluminescence) is the emission of light (luminescence) as the result of a chemical reaction, i.e. a chemical reaction results in a flash or glow of light. A standard example of chemiluminescence in the laboratory se ...

glow stick A glow stick, also known as a light stick, chem light, light wand, light rod, and rave light, is a self-contained, short-term light-source. It consists of a translucent plastic tube containing isolated substances that, when combined, make light ...

s. It can be synthesized by reacting 2-carbopentoxy-3,5,6-trichlorophenol with

oxalyl chloride Oxalyl chloride is an organic chemical compound with the formula . This colorless, sharp-smelling liquid, the diacyl chloride of oxalic acid, is a useful reagent in organic synthesis. Preparation Oxalyl chloride was first prepared in 1892 by the ...

. When mixed with hydrogen peroxide in an organic solvent (diethyl phthalate, ethyl acetate, etc...) in the presence of a fluorescent dye CPPO causes the emission of light, following its degradation to 1,2-dioxetanedione (note that many side-groups of the aromatic rings are not shown.): : The reaction rate is pH dependent, and slightly alkaline conditions achieved by adding a weak base, e.g.

sodium salicylate Sodium salicylate is a sodium salt of salicylic acid. It can be prepared from sodium phenolate and carbon dioxide under higher temperature and pressure. Historically, it has been synthesized by refluxing methyl salicylate (wintergreen oil) with ...

, will produce brighter light. Developed by

American Cyanamid American Cyanamid Company was an American manufacturing conglomerate. It began as a fertilizer company and added many additional lines of business before merging with American Home Products in 1994. The combined company sold off most of its di ...

in the 1960s, the formulation containing CPPO, a fluorescer, and a glass capsule containing

hydrogen peroxide Hydrogen peroxide is a chemical compound with the formula . In its pure form, it is a very pale blue liquid that is slightly more viscosity, viscous than Properties of water, water. It is used as an oxidizer, bleaching agent, and antiseptic, usua ...

and a base catalyst, all in dialkyl

phthalate Phthalates ( ), or phthalate esters, are esters of phthalic acid. They are mainly used as plasticizers, i.e., substances added to plastics to increase their flexibility, transparency, durability, and longevity. They are used primarily to soften ...

solvents, was marketed as Cyalume. The following colors can be produced by using different dyes:

References

{{reflist Oxalate esters Phenol esters Chemiluminescence