M. Dubreuil, E. Goethals
Oct 1, 1997
Citations
0
Influential Citations
22
Citations
Journal
Macromolecular Chemistry and Physics
Abstract
Functional esters of trifluoromethanesulfonic acid (triflate esters) have been synthesized by reaction of functional alcohols (allyl alcohol, 2-hydroxyethyl acrylate (HEA) and methacrylate (HEMA), 4-hydroxybutyl acrylate (HBA)) with triflic anhydride in the presence of 2,6-di-tert-butylpyridine. These esters were used in situ as initiators for the polymerization of tetrahydrofuran (THF), with the purpose to synthesize endgroup-functionalized polyTHF's. The method was first tested with the system butanol/triflic anhydride. With this combination, quantitative formation of the ester and, subsequently, controlled polymerization of THF was realized. Similar results were obtained with the system allyl alcohol/triflic anhydride. With 2-hydroxyethyl acrylate (HEA) and 2-hydroxyethyl methacrylate (HEMA), the synthesis of the triflate ester was accompanied by the formation of substantial amounts of ether formed by reaction of the triflate ester with a second molecule of alcohol. This was attributed to an enhanced reactivity of the triflate ester due to nucleophilic assistance by the carbonyl group in y-position. This assistance is not possible with 4-hydroxybutyl acrylate (HBA) and with this alcohol, the formation of the ester was almost quantitative. The synthesis of polyTHF acrylate macromonomer was successful with the latter system.