Telomerization

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]