Organic reactions

thumb|Burning pieces of wood, showing various stages of pyrolysis, followed by oxidative combustion

thermal or catalytic decomposition of a compound such as a hydrocarbon into chemical species of smaller molecular weight

In chemistry, halogenation is a chemical reaction which introduces one or more halogens into a chemical compound. Halide-containing compounds are pervasive, making this type of transformation important, e.g. in the production of polymers, drugs. This kind of conversion is in fact so common that a comprehensive overview is challenging. This article mainly deals with halogenation using elemental halogens (). Halides are also commonly introduced using halide salts and hydrogen halide acids. Many specialized reagents exist for introducing halogens into diverse substrates, e.g. thionyl chloride.

In chemistry, disproportionation, sometimes called dismutation (the French word), is a redox reaction in which one compound of intermediate oxidation state converts to two compounds, one of higher and one of lower oxidation state. The reverse of disproportionation, such as when a compound in an intermediate oxidation state is formed from precursors of lower and higher oxidation states, is called comproportionation, also known as symproportionation.

thumb|upright=1.5|Typical route for alkylation of benzene with ethylene and ZSM-5 as a heterogeneous catalystAlkylation is a chemical reaction that entails transfer of an alkyl group. The alkyl group may be transferred as an alkyl carbocation, a free radical, a carbanion, or a carbene (or their equivalents). Alkylating agents are reagents for effecting alkylation. Alkyl groups can also be removed in a process known as dealkylation. Alkylating agents are often classified according to their nucleophilic or electrophilic character. In oil refining contexts, alkylation refers to a particular alkyl

Methylation, in the chemical sciences, is the addition of a methyl group on a substrate, or the substitution of an atom (or group) by a methyl group. Methylation is a form of alkylation, with a methyl group replacing a hydrogen atom. These terms are commonly used in chemistry, biochemistry, soil science, and biology.

class=skin-invert-image|thumb|400px|Salicylic acid is acetylated with acetic anhydride to form [[aspirin and acetic acid as a byproduct]]

Glycosylation is the reaction in which a carbohydrate (or 'glycan'), i.e. a glycosyl donor, is attached to a hydroxyl or other functional group of another molecule (a glycosyl acceptor) in order to form a glycoconjugate. In biology (but not always in chemistry), glycosylation usually refers to an enzyme-catalysed reaction, whereas glycation (also 'non-enzymatic glycation' and 'non-enzymatic glycosylation') may refer to a non-enzymatic reaction.

In chemistry, acylation is a broad class of chemical reactions in which an acyl group () is added to a substrate. The compound providing the acyl group is called the acylating agent. The substrate to be acylated and the product include the following: alcohols, esters amines, amides arenes or alkenes, ketones A particularly common type of acylation is acetylation, the addition of the acetyl group. Closely related to acylation is formylation, which employ sources of "HCO+ in place of "RCO+".

thumb|right|300px|Aminotransfer reaction between an amino acid and an alpha-keto acid

chemical reaction involving organic compounds

Carboxylation is a chemical reaction in which a carboxylic acid is produced by treating a substrate with carbon dioxide. The opposite reaction is decarboxylation. In chemistry, the term carbonation is sometimes used synonymously with carboxylation, especially when applied to the reaction of carbanionic reagents with CO2. More generally, carbonation usually describes the production of carbonates.

molecular fragment that departs with a pair of electrons in heterolytic bond cleavage

Demethylation is the chemical process resulting in the removal of a methyl group (CH3) from a molecule. A common way of demethylation is the replacement of a methyl group by a hydrogen atom, resulting in a net loss of one carbon and two hydrogen atoms.

degradation

chemical reaction

chemical reaction

right|400px In organic chemistry, hydroboration refers to the addition of a hydrogen-boron bond to certain double and triple bonds involving carbon (, , , and ). This chemical reaction is useful in the organic synthesis of organic compounds.

Amination is the process by which an amine group is introduced into an organic molecule. This type of reaction is important because organonitrogen compounds are pervasive.

chemical reaction

photochemical reaction

organic synthesis

organic reaction in which indigo is prepared from 2-nitrobenzaldehyde and acetone

chemical reaction involving the formation of sugars from formaldehyde

chemical reaction

chemical reaction (disproportionation of an aldehyde in the presence of an alkoxide)

thumb|right|300px|Resonance structures of an enolate anion.

process of converting organic compounds into nitroso derivatives

Glucuronidation is often involved in drug metabolism of substances such as drugs, pollutants, bilirubin, androgens, estrogens, mineralocorticoids, glucocorticoids, fatty acid derivatives, retinoids, and bile acids. These linkages involve glycosidic bonds.

palladium-catalysed substitution reaction

chemical reaction

Name reactions

In chemistry, oxychlorination is a process for generating the equivalent of chlorine gas (Cl2) from hydrogen chloride and oxygen. This process is attractive industrially because hydrogen chloride is less expensive than chlorine.

chemical reaction

vacuum pyrolysis reaction

Method of synthesizing an isocyanide

Reaction

organic chemical reaction

Methanation is the conversion of carbon monoxide and carbon dioxide (COx) to methane (CH4) through hydrogenation. The methanation reactions of COx were first discovered by Sabatier and Senderens in 1902.

chemical reaction

thumb|400px|The recovery of methionine from [[homocysteine by transmethylation is depicted in reaction 4. The transmethylation cycle is depicted in reactions 1–4.]]

chemical process

chemical reaction involving free radicals. This reaction type is abundant in organic reactions

right|frameless|550x550px A carbometallation is any reaction where a carbon-metal bond reacts with a carbon-carbon π-bond to produce a new carbon-carbon σ-bond and a carbon-metal σ-bond. The resulting carbon-metal bond can undergo further carbometallation reactions (oligomerization or polymerization see Ziegler-Natta polymerization) or it can be reacted with a variety of electrophiles including halogenating reagents, carbonyls, oxygen, and inorganic salts to produce different organometallic reagents. Carbometallations can be performed on alkynes and alkenes to form products with high geometric

reaction in organic chemistry

organic reaction for the decarboxylation of carboxylic acids to alkyl halides

reaction in organic chemistry

inorganic chemical reaction

a rearrangement reaction

chemical reaction

Biological processes used in gene regulation

organic reaction

Chemical reaction

thumb|Scheme for dehalogenation reaction (R = alkyl or [[aryl group, X = I, Cl, Br, F)]]

isomerization reaction