Perfluoro-2-methyl-2-pentene

clear colourless to light yellow liquid

Hexafluoropropene Dimer is used in the production of waterproof and oilproof Si/F-modified polyurethane finishing agent for textile and leather. Hexafluoropropene Dimer is also used as a blowing agent for manufacture of polyurethane foams.

Perfluoro-2-methyl-2-pentene reacts withα-oxides in the presence of CsF, like perfluoro isobutylene. Olefins containing a perfluoro(dimethylpropyl)methyl group and cesium perfluoro-2-methyl-penten-3-olate are formed.
The reaction of this compound with epichlorohydrin in the presence of CSP results in the formation of trans-1,1,1,7,7,8,8,9,9,9-decafluoro-2,6,6-tris(trifluoromethyl)-4-nonene, 2-fluoro-2-pentafluoroethyl-3,3-bis(trifluoromethyl)-5-[α,α-(hydro-β,β-bis(trifluoromethyl)perfluoroamyl] tetrahydrofuran, and 2-H-perfluoro-2-methylpentane.
The hexafluoropropylene dimer perfluoro-2-methyl-2-pentene is partially converted under the action of CsF into the thermodynamically most stable hexafluoropropylene trimer perfluoro-2,4-dimiethyl-3-heptene[1].
It reacts with alcohols to give either fluorine substitution products or addition products, depending on the amount of essential catalyst used. Alcohols containing branched substituents give another product in addition to those derived from the substitution of a vinyl fluorine atom in perfluoro-2-methyl-2-pentene, namely isomeric vinyl ethers, which are derivatives of perfluoro-2-methyl-1-pentene[2].

[1] L. L. Gervits, I. L. Knunyants, K. N. Makarov. “Reaction of perfluoro-2-methyl-2-pentene and perfluoroisobutylene with α-oxides in the presence of cesium fluoride.” Russian Chemical Bulletin 30 5 (1981): 846–852.
[2] V. F. Snegirev, K. N. Makarov. “Reaction of perfluoro-2-methylpent-2-ene with oxygen nucleophiles.” Russian Chemical Bulletin 35 1 (1986): 91–103.