Condensation reaction
A condensation reaction is a chemical reaction in which two molecules of the elimination of water - Alternatively, ammonia, carbon dioxide, hydrogen chloride, an alkanol or an other low molecular weight material - together. Condensation reactions are also possible, and often run intramolecular reversible.
An example of the condensation reaction, the enzyme-catalyzed reaction between two amino acids to a dipeptide according to the following reaction scheme:
The condensation is important in organic chemistry. These include the following reactions:
- Aldol condensation
- Acyloin condensation
- Claisen condensation
- Dieckmann condensation
- Ether
- Nukleotidbildung
- Peptide and protein formation
- Polycondensation for plastics manufacturing
- Esterification
The condensation reaction is the basis for the production of many high molecular weight compounds, for example, nylon, polyester, and of different epoxides, as well as silicates and polyphosphates. The synthesis of biopolymers ( proteins, polysaccharides, lipids, nucleic acids) in the metabolism of the cells is performed by condensation reactions.
The reaction to react with the monomers to form a polymer, it is called polycondensation. In contrast to the other types of polymer production ( polymerization and polyaddition) are used in the polycondensation of one or more byproducts, the condensate ( water, ammonia, alcohols or other ) release. These by-products must be removed continuously to obtain a high conversion ( law of mass action ). The reaction conversion of a polycondensation must clearly be above 95 %, as otherwise receive only short-chain oligomers ( Carothers equation). Thus, a monomer can participate in the reaction, it must have at least two functional groups which are reactive (e.g.,- OH,-COOH ,-CO ,-NH 2, ...).