Liposomes by polymerization of an imidazolium ionic liquid: use as microreactors for gold-catalyzed alcohol oxidation.

The bipodal ionic liquid N,N'-bis(10-undecenyl)-2-methylimidazolium underwent polymerization in aqueous media with potassium persulfate to form submicrometric liposomes. A TEM study indicated that the liposomes are the result of several morphological transformations of the polymer particles. Photopolymerization at room temperature led to spherical particles with some internal voids and polymer chains. We took advantage of the positive charge on the imidazolium rings and used a photocuring agent to form in a single step starting from the imidazolium monomer and NaAuCl(4) spherical polymer particles containing gold nanoparticles (10-15 nm) in their interior. This system was found to promote the selective aerobic oxidation of 2-hydroxybenzyl alcohol to salicylaldehyde.