The group R-C=O is called an acyl group, the general structure of carboxylic acid derivatives is R-C(=O)-Y, for example:
| Group Name | Formula |
|---|---|
| Halogen Anhydrides | R-C(=O)-X, X - halogen |
| Carboxylic acidAnhydrides | R-C(=O)-O=C=O-R |
| Esters | R-C(=O)-O-R |
| Amides | R-C(=O)-NH2(R,R) |
| Table 1. Derivatives of carboxylic acids | |
Esters
Ethyl acetate, butyl acetate, isobutyl acetate, as well as their mixtures are widely used as solvents of paint and varnish products. Vinyl acetate and acetate propionate are used in the production of plastic, such monomers are obtained by the Wacker process: oxidation of a mixture of ethylene and acetic acid in the presence of a catalyst:
In the presence of PdCl2, CuCl2
H2C=CH2 + HO-C(=O)-CH3 + ½O2 → H2C=CH-O-C(=O)-CH3 (vinyl acetate) + H2O
Certain esters are used for the production and modification of lubricants, to impart a certain viscosity. For example, pentaerythritol permanganate is used for lubrication in jet aircraft.
Esters with nitric acid are explosives, the three most used are glycyrine trinitrate (nitroglycerin), used in mines and in engineering works; glycol dinitrate (nitroglycol), used as a detonator. Pentaerythritol tetranitrate - one of the most powerful modern explosives.
Esters are also used to give flexibility to plastics. Some esters have a pleasant smell and are used in perfumery and the food industry.
Amides
Formamide is obtained by mixing carbon monoxide and ammonia in the presence of CH3O+ and at a pressure of 50 atm. Formamide it is used as a solvent. Another amide is dimethylformamide, used in laboratories and in industry as a solvent, dissolves a large number of polar and weakly polar compounds. Dimethylformamide is obtained by mixing carbon monoxide with dimethylamine, in the presence of a rhodium catalyst at high pressure.
What esters and amides look like
Нажмите на молекулу в списке и 3D-модель появится в оранжевом окне
