Carboxylic ester

In chemistry, an ester is a chemical compound derived from an acid (organic or inorganic) in which at least one –OH (hydroxyl) group is replaced by an –O–alkyl (alkoxy) group. Usually, esters are derived from a carboxylic acid and an alcohol. Glycerides, which are fatty acid esters of glycerol, are important esters in biology, being one of the main classes of lipids, and making up the bulk of animal fats and vegetable oils. Esters with low molecular weight are commonly used as fragrances and found in essential oils and pheromones. Phosphoesters form the backbone of DNA molecules. Nitrate esters, such as nitroglycerin, are known for their explosive properties, while polyesters are important plastics, with monomers linked by ester moieties. Esters usually have a sweet smell and are considered high-quality solvents for a broad array of plastics, plasticizers, resins, and lacquers. They are also one of the largest classes of synthetic lubricants on the commercial market.b. Ester oder sauerstoffsäure Aetherarten.Ethers du troisième genre.Viele mineralische und organische Sauerstoffsäuren treten mit einer Alkohol-Art unter Ausscheidung von Wasser zu neutralen flüchtigen ätherischen Verbindungen zusammen, welche man als gepaarte Verbindungen von Alkohol und Säuren-Wasser oder, nach der Radicaltheorie, als Salze betrachten kann, in welchen eine Säure mit einem Aether verbunden ist. b. Ester or oxy-acid ethers.Ethers of the third type.Many mineral and organic acids containing oxygen combine with an alcohol upon elimination of water to neutral, volatile ether compounds, which one can view as coupled compounds of alcohol and acid-water, or, according to the theory of radicals, as salts in which an acid is bonded with an ether. In chemistry, an ester is a chemical compound derived from an acid (organic or inorganic) in which at least one –OH (hydroxyl) group is replaced by an –O–alkyl (alkoxy) group. Usually, esters are derived from a carboxylic acid and an alcohol. Glycerides, which are fatty acid esters of glycerol, are important esters in biology, being one of the main classes of lipids, and making up the bulk of animal fats and vegetable oils. Esters with low molecular weight are commonly used as fragrances and found in essential oils and pheromones. Phosphoesters form the backbone of DNA molecules. Nitrate esters, such as nitroglycerin, are known for their explosive properties, while polyesters are important plastics, with monomers linked by ester moieties. Esters usually have a sweet smell and are considered high-quality solvents for a broad array of plastics, plasticizers, resins, and lacquers. They are also one of the largest classes of synthetic lubricants on the commercial market. The word ester was coined in 1848 by a German chemist Leopold Gmelin, probably as a contraction of the German Essigäther, 'acetic ether'. Ester names are derived from the parent alcohol and the parent acid, where the latter may be organic or inorganic. Esters derived from the simplest carboxylic acids are commonly named according to the more traditional, so-called 'trivial names' e.g. as formate, acetate, propionate, and butyrate, as opposed to the IUPAC nomenclature methanoate, ethanoate, propanoate and butanoate. Esters derived from more complex carboxylic acids are, on the other hand, more frequently named using the systematic IUPAC name, based on the name for the acid followed by the suffix -oate. For example, the ester hexyl octanoate, also known under the trivial name hexyl caprylate, has the formula CH3(CH2)6CO2(CH2)5CH3. The chemical formulas of organic esters usually take the form RCO2R′, where R and R′ are the hydrocarbon parts of the carboxylic acid and the alcohol, respectively. For example, butyl acetate (systematically butyl ethanoate), derived from butanol and acetic acid (systematically ethanoic acid) would be written CH3CO2C4H9. Alternative presentations are common including BuOAc and CH3COOC4H9. Cyclic esters are called lactones, regardless of whether they are derived from an organic or an inorganic acid. One example of an organic lactone is γ-valerolactone. An uncommon class of organic esters are the orthoesters, which have the formula RC(OR′)3. Triethylorthoformate (HC(OC2H5)3) is derived, in terms of its name (but not its synthesis) from orthoformic acid (HC(OH)3) and ethanol. Esters can also be derived from an inorganic acid and an alcohol. Thus, the nomenclature extends to inorganic oxo acids and their corresponding esters: phosphoric acid and phosphate esters/organophosphates, sulfuric acid and sulfate esters/organosulfates, nitric acid and nitrate, and boric acid and borates. For example, triphenyl phosphate is the ester derived from phosphoric acid and phenol. Organic carbonates are derived from carbonic acid; for example, ethylene carbonate is derived from carbonic acid and ethylene glycol. So far an alcohol and inorganic acid are linked via oxygen atoms. The definition of inorganic acid ester that feature inorganic chemical elements links between alcohols and the inorganic acid – the phosphorus atom linking to three alkoxy functional groups in organophosphate – can be extended to the same elements in various combinations of covalent bonds between carbons and the central inorganic atom and carbon–oxygen bonds to central inorganic atoms. For example, phosphorus features three carbon–oxygen–phosphorus bonds and one phosphorus–oxygen double bond in organophosphates, three carbon–oxygen–phosphorus bonds and no phosphorus–oxygen double bonds in phosphite esters or organophosphites, two carbon–oxygen–phosphorus bonds, no phosphorus–oxygen double bonds but one phosphorus–carbon bond in phosphonites, one carbon–oxygen–phosphorus bonds, no phosphorus–oxygen double bonds but two phosphorus–carbon bonds in phosphinites. In corollary, boron features borinic esters (n = 2), boronic esters (n = 1), and borates (n = 0).