Telomerization

This article is about the polymerization reaction. For the DNA component, see telomere.

Telomerization is a reaction that produces a particular kind of oligomer with two distinct end groups. The oligomer is called a telomer.^[1] Some telomerizations proceed by radical pathways, many do not. A generic equation is:

${\displaystyle {\ce {A-B + n M -> A-M_{n}-B}}}$

where M is the monomer, and A and B are the end groups, and n is the degree of polymerization.

One example is the coupled dimerization and hydroesterification of buta-1,3-diene. This step produces a doubly unsaturated C9-ester:^[2]

2 CH₂=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 and the carboxy methyl (CO₂CH₃). This and several related reactions proceed with palladium catalysts.^[3] Many telomerizations are used in industrial chemistry.^[4]

Nomenclature

According to the jargon in polymer chemistry, telomerization requires a telogen to react with at least one unsaturated taxogen molecule.^[4] Fluorotelomers are an example.

See also

• Perfluorooctanoic acid (synthesis)
• Telomerization (dimerization)

References

1. IUPAC, Compendium of Chemical Terminology, 2nd ed. (the "Gold Book") (1997). Online corrected version: (2006–) "telomerization". doi:10.1351/goldbook.T06260
2. J. Grub; E. Löser (2012). "Butadiene". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a04_431.pub2. ISBN 978-3527306732.
3. Kiss, Gabor (2001). "Palladium-Catalyzed Reppe Carbonylation". Chemical Reviews. 101 (11): 3435–3456. doi:10.1021/cr010328q. PMID 11840990.
4. Lehmler, HJ (Mar 2005). "Synthesis of environmentally relevant fluorinated surfactants—a review". Chemosphere. 58 (11): 1471–96. Bibcode:2005Chmsp..58.1471L. doi:10.1016/j.chemosphere.2004.11.078. PMID 15694468.