Telomerization is a

reaction Reaction may refer to a process or to a response to an action, event, or exposure: Physics and chemistry *Chemical reaction * Nuclear reaction *Reaction (physics), as defined by Newton's third law * Chain reaction (disambiguation). Biology and ...

that produces a particular kind of

oligomer In chemistry and biochemistry, an oligomer () is a molecule that consists of a few repeating units which could be derived, actually or conceptually, from smaller molecules, monomers.Quote: ''Oligomer molecule: A molecule of intermediate relativ ...

with two distinct end groups. The oligomer is called a telomer. Some telomerizations proceed by radical pathways, many do not. A generic equation is: : A-B + n M -> A-M_-B where M is the monomer, and A and B are the end groups, and n is the

degree of polymerization The degree of polymerization, or DP, is the number of monomeric units in a macromolecule or polymer or oligomer molecule. For a homopolymer, there is only one type of monomeric unit and the ''number-average'' degree of polymerization is given ...

. One example is the coupled dimerization and

hydroesterification In industrial chemistry, carboalkoxylation is a process for converting alkenes to esters. This reaction is a form of carbonylation. A closely related reaction is hydrocarboxylation, which employs water in place of alcohols A commercial applicatio ...

of 1,3-

butadiene 1,3-Butadiene () is the organic compound with the formula (CH2=CH)2. It is a colorless gas that is easily condensed to a liquid. It is important industrially as a precursor to synthetic rubber. The molecule can be viewed as the union of two viny ...

. This step produces a doubly unsaturated C9-ester: :2CH₂=CH-CH=CH₂ + CO + CH₃OH → CH₂=CH(CH₂)₃CH=CHCH₂CO₂CH₃ The monomer in this reaction is butadiene, the degree of polymerization is 2, and the end groups are

vinyl Vinyl may refer to: Chemistry * Polyvinyl chloride (PVC), a particular vinyl polymer * Vinyl cation, a type of carbocation * Vinyl group, a broad class of organic molecules in chemistry * Vinyl polymer, a group of polymers derived from vinyl m ...

and the carboxy methyl (CO₂CH₃). This and several related reactions proceed with

palladium Palladium is a chemical element with the symbol Pd and atomic number 46. It is a rare and lustrous silvery-white metal discovered in 1803 by the English chemist William Hyde Wollaston. He named it after the asteroid Pallas, which was itself ...

catalysts. Many telomerizations are used in industrial chemistry.

Nomenclature

According to the jargon in polymer chemistry, telomerization requires a telogen to react with at least one unsaturated taxogen molecule.

Fluorotelomer Fluorotelomers are fluorocarbon-based oligomers, or telomers, synthesized by telomerization. Some fluorotelomers and fluorotelomer-based compounds are a source of environmentally persistent perfluorinated carboxylic acids such as PFOA and PFNA, ...

s are an example.

References

Chemical synthesis Chemical processes Industrial processes Polymer chemistry Oligomers {{reaction-stub

Nomenclature

See also

References