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Encyclopedia > Condensation reaction

A condensation reaction is a chemical reaction in which two molecules or moieties combine to form one single molecule, together with the loss of a small molecule.[1] When this small molecule is water, it is known as a dehydration reaction; other possible small molecules lost are hydrogen chloride, methanol, or acetic acid. For other uses, see Chemical reaction (disambiguation). ... 3D (left and center) and 2D (right) representations of the terpenoid molecule atisane. ... In organic chemistry, functional groups (or moieties) are specific groups of atoms within molecules, that are responsible for the characteristic chemical reactions of those molecules. ... In chemistry, a dehydration reaction is a chemical reaction that involves the loss of water from the reacting molecule. ... R-phrases , S-phrases , , , , Flash point non-flammable Supplementary data page Structure and properties n, εr, etc. ... Methanol, also known as methyl alcohol, carbinol, wood alcohol, wood naptha or wood spirits, is a chemical compound with chemical formula CH3OH. It is the simplest alcohol, and is a light, volatile, colourless, flammable, poisonous liquid with a distinctive odor that is somewhat milder and sweeter than ethanol (ethyl alcohol). ... Acetic acid, also known as ethanoic acid, is an organic chemical compound with the formula CH3COOH best recognized for giving vinegar its sour taste and pungent smell. ...

The condensation of two amino acids to form a peptide bond.
The condensation of two amino acids to form a peptide bond.

A condensation reaction may be considered as the opposite of a hydrolysis reaction (the cleavage of a chemical entity into two parts by the action of water). Download high resolution version (1181x354, 6 KB)Created from editing of by Luke Surl. ... Download high resolution version (1181x354, 6 KB)Created from editing of by Luke Surl. ... This article is about the class of chemicals. ... A peptide bond is a chemical bond that is formed between two molecules when the carboxyl group of one molecule reacts with the amino group of the other molecule, releasing a molecule of water (H2O). ... Hydrolysis is a chemical reaction or process in which a chemical compound reacts with water. ...


Mechanism

Many condensation reactions follow a nucleophilic acyl substitution or an aldol condensation reaction mechanism. Other condensations, such as the acyloin condensation are triggered by radical or single electron transfer conditions. Nucleophilic acyl substitution is a type of substitution reaction between nucleophiles and acyl compounds. ... An Aldol condensation is an organic reaction where an enolate ion reacts with a carbonyl compound to form a β-hydroxyaldehyde or β-hydroxyketone followed by dehydration to a conjugated enone. ... In chemistry, a reaction mechanism is the step by step sequence of elementary reactions by which overall chemical change occurs. ... In chemistry, the acyloin condensation is a reductive coupling of two carboxylic esters using metallic sodium to give an α-hydroxyketone, also known as an acyloin. ... In chemistry, radicals (often referred to as free radicals) are atomic or molecular species with unpaired electrons on an otherwise open shell configuration. ... A one-electron reduction in organic chemistry involves the transfer of an electron from a metal to an organic substrate. ...


The synthesis of polymers, where monomers react and become covalently bonded with one another through the loss of a water molecule.


Condensation reactions in polymer chemistry

In polymer chemistry, a series of condensation reactions take place whereby monomers or monomer chains add to each other to form longer chains. This may also be termed as 'condensation polymerization' or 'step-growth polymerization'. It occurs either as a homopolymerization of an A-B monomer or a polymerization of two co-monomers A-A and B-B. Small molecule condensates are usually liberated, unlike in polyaddition where there is no liberation of small molecules.


A high conversion rate is required to achieve high molecular weights as per Carothers' equation. In step-growth polymerization, Carothers equation gives the number-average degree of polymerization, Xn, for a given fractional monomer conversion, p. ...


In general, condensation polymers form more slowly than addition polymers, often requiring heat. They are generally lower in molecular weight. Monomers are consumed early in the reaction; the terminal functional groups remain active throughout and short chains combine to form longer chains. Bifunctional monomers lead to linear chains (and therefore thermoplastic polymers), but when the monomer functionality exceeds two, the product is a thermoset polymer.


Applications

This type of reaction is used as a basis for the making of many important polymers for example: nylon, polyester and other condensation polymers and various epoxies. It is also the basis for the laboratory formation of silicates and polyphosphates. The reactions that form acid anhydrides from their constituent acids are typically condensation reactions. Other organic condensation reactions are Aldol condensations, self-condensation, the acyloin condensation and the benzoin condensation. A polymer (from Greek: πολυ, polu, many; and μέρος, meros, part) is a substance composed of molecules with large molecular mass composed of repeating structural units, or monomers, connected by covalent chemical bonds. ... For other uses of this word, see nylon (disambiguation). ... SEM picture of a bend in a high surface area polyester fiber with a seven-lobed cross section Polyester is a category of polymers, or, more specifically condensation polymers, which contain the ester functional group in their main chain. ... Condensation polymers are any class of polymers formed through a condensation reaction, releasing (or condensing) a small molecule by-product such as water or methanol, as opposed to addition polymers which involve the reaction of unsaturated monomers. ... In chemistry, epoxy or polyepoxide is a thermosetting epoxide polymer that cures (polymerizes and crosslinks) when mixed with a catalyzing agent or hardener. Most common epoxy resins are produced from a reaction between epichlorohydrin and bisphenol-A. The first commercial attempts to prepare resins from epichlorohydrin occurred in 1927 in... In chemistry, a silicate is a compound containing an anion in which one or more central silicon atoms are surrounded by electronegative ligands. ... Polyphosphates are phosphate polymers linked between hydroxyl groups and hydrogen atoms. ... Structure of anhydride. ... An Aldol condensation is an organic reaction where an enolate ion reacts with a carbonyl compound to form a β-hydroxyaldehyde or β-hydroxyketone followed by dehydration to a conjugated enone. ... Self-condensation is an organic reaction where a chemical compound containing a carbonyl group acts both as the electrophile and the nucleophile in a aldol condensation. ... In chemistry, the acyloin condensation is a reductive coupling of two carboxylic esters using metallic sodium to give an α-hydroxyketone, also known as an acyloin. ... The Benzoin condensation is a condensation reaction between two aromatic aldehydes, especially benzaldehyde that is catalyzed by a cyanide. ...


Many biological transformations are condensation reactions. Polypeptide synthesis, polyketide synthesis, terpene syntheses, phosphorylation, and glycosylations are a few examples. An overview of protein synthesis. ... Polyketides are secondary metabolites from bacteria, fungi, plants, and animals. ... Many terpenes are derived from conifer resins, here a pine. ... A phosphorylated serine residue Phosphorylation is the addition of a phosphate (PO4) group to a protein or a small molecule or the introduction of a phosphate group into an organic molecule. ... Glycosylation is the process or result of addition of saccharides to proteins and lipids. ...


[[Media:Example.ogg ---- Insert non-formatted text here#REDIRECT [[<s>Insert text</s><br /><sup><sub>Superscript text</sub><small><!-- Small Text --> <gallery> <blockquote> Image:Example.jpg|Caption1 Image:Example.jpg|Caption2 </blockquote>{| class="wikitable" |- ! header 1 ! header 2 ! header 3 |- | row 1, cell 1 | row 1, cell 2 | row 1, cell 3 |- | row 2, cell 1 | row 2, cell 2 | row 2, cell 3 |} </gallery></small></sup>]]]]==References==

  1. ^ International Union of Pure and Applied Chemistry (1994). "Condensation Reaction". Compendium of Chemical Terminology Internet edition.

  Results from FactBites:
 
Condensation reaction - definition of Condensation reaction in Encyclopedia (163 words)
A condensation reaction (also known as a dehydration reaction) is a chemical reaction in which two molecules or moieties react with each other with the concurrent loss of water or ammonia.
It may be considered as the opposite of a hydrolysis reaction, ie, the cleavage of a chemical entity into two parts by the action of water.
The reactions that form acid anhydrides from their constituent acids are typically condensation reactions.
  More results at FactBites »

 
 

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