Propiolic acid is the organic compound with the formula HC₂CO₂H. It is the simplest

acetylenic In organic chemistry, the term acetylenic designates *A doubly unsaturated position (''sp''-hybridized) on a molecular framework, for instance in an alkyne such as acetylene; *An ethynyl fragment, HC\equivC–, or substituted homologue. See also ...

carboxylic acid In organic chemistry, a carboxylic acid is an organic acid that contains a carboxyl group () attached to an R-group. The general formula of a carboxylic acid is or , with R referring to the alkyl, alkenyl, aryl, or other group. Carboxylic ...

. It is a colourless liquid that crystallises to give silky crystals. Near its boiling point, it decomposes. It is soluble in water and possesses an odor like that of

acetic acid Acetic acid , systematically named ethanoic acid , is an acidic, colourless liquid and organic compound with the chemical formula (also written as , , or ). Vinegar is at least 4% acetic acid by volume, making acetic acid the main component ...

Preparation

It is prepared commercially by oxidizing

propargyl alcohol Propargyl alcohol, or 2-propyn-1-ol, is an organic compound with the chemical formula, formula C3H4O. It is the simplest stable Alcohol (chemistry), alcohol containing an alkyne functional group. Propargyl alcohol is a colorless viscous liquid t ...

at a lead electrode. It can also be prepared by

decarboxylation Decarboxylation is a chemical reaction that removes a carboxyl group and releases carbon dioxide (CO2). Usually, decarboxylation refers to a reaction of carboxylic acids, removing a carbon atom from a carbon chain. The reverse process, which is t ...

acetylenedicarboxylic acid Acetylenedicarboxylic acid or butynedioic acid is an organic compound (a dicarboxylic acid) with the formula C4H2O4 or . It is a crystalline solid that is soluble in diethyl ether. The removal of two protons yields the acetylenedicarboxylate di ...

. :

Reactions and applications

Exposure to

sunlight Sunlight is a portion of the electromagnetic radiation given off by the Sun, in particular infrared, visible, and ultraviolet light. On Earth, sunlight is scattered and filtered through Earth's atmosphere, and is obvious as daylight when t ...

converts it into

trimesic acid Trimesic acid, also known as benzene-1,3,5-tricarboxylic acid, is an organic compound with the formula C6H3(CO2H)3. It is one of three isomers of benzenetricarboxylic acid. A colorless solid, trimesic acid has some commercial value as a precursor t ...

(benzene-1,3,5-tricarboxylic acid). It undergoes

bromination In chemistry, halogenation is a chemical reaction that entails the introduction of one or more halogens into a compound. Halide-containing compounds are pervasive, making this type of transformation important, e.g. in the production of polymers, ...

to give dibromoacrylic acid. With

hydrogen chloride The compound hydrogen chloride has the chemical formula and as such is a hydrogen halide. At room temperature, it is a colourless gas, which forms white fumes of hydrochloric acid upon contact with atmospheric water vapor. Hydrogen chloride ga ...

it forms chloroacrylic acid. Its

ethyl ester In chemistry, an ester is a compound derived from an oxoacid (organic or inorganic) in which at least one hydroxyl group () is replaced by an alkoxy group (), as in the substitution reaction of a carboxylic acid and an alcohol. Glycerides are ...

condenses with

hydrazine Hydrazine is an inorganic compound with the chemical formula . It is a simple pnictogen hydride, and is a colourless flammable liquid with an ammonia-like odour. Hydrazine is highly toxic unless handled in solution as, for example, hydrazine ...

to form

pyrazolone Pyrazolone is 5-membered heterocycle containing two adjacent nitrogen atoms. It can be viewed as a derivative of pyrazole possessing an additional carbonyl (C=O) group. Compounds containing this functional group are useful commercially in analgesic ...

. It forms a characteristic explosive solid upon treatment to its

aqueous solution An aqueous solution is a solution in which the solvent is water. It is mostly shown in chemical equations by appending (aq) to the relevant chemical formula. For example, a solution of table salt, or sodium chloride (NaCl), in water would be re ...

with

ammoniacal Ammonia is an inorganic compound of nitrogen and hydrogen with the formula . A stable binary hydride, and the simplest pnictogen hydride, ammonia is a colourless gas with a distinct pungent smell. Biologically, it is a common nitrogenous was ...

silver nitrate Silver nitrate is an inorganic compound with chemical formula . It is a versatile precursor to many other silver compounds, such as those used in photography. It is far less sensitive to light than the halides. It was once called ''lunar caustic' ...

. An amorphous explosive

precipitate In an aqueous solution, precipitation is the process of transforming a dissolved substance into an insoluble solid from a super-saturated solution. The solid formed is called the precipitate. In case of an inorganic chemical reaction leading ...

forms with ammoniacal

cuprous chloride Copper(I) chloride, commonly called cuprous chloride, is the lower chloride of copper, with the formula CuCl. The substance is a white solid sparingly soluble in water, but very soluble in concentrated hydrochloric acid. Impure samples appear gre ...

Propiolates

Propiolates are esters or salts of propiolic acid. Common examples include

methyl propiolate Methyl propiolate is an organic compound with the formula HC2CO2CH3. It is the methyl ester of propiolic acid, the simplest acetylenic carboxylic acid. It is a colorless liquid that is miscible with organic solvents. The compound is a reagent a ...

and

ethyl propiolate Ethyl propiolate is an organic compound with the formula HC2CO2C2H5. It is the ethyl ester of propiolic acid, the simplest acetylenic carboxylic acid In organic chemistry, a carboxylic acid is an organic acid that contains a carboxyl grou ...

References

{{DEFAULTSORT:Propiolic Acid Carboxylic acids Alkyne derivatives