Increased conversion to 2,4,6-triarylpyrylium salt:: Aldol cyclotrimerization of acetophenone in BMImP6 ionic liquid

Substituted acetophenone 1 in BMImPF(6) ionic liquid, heated at 120 degrees C for 24 h, produces beta-methylchalcone 2, triarylbenzene 3, and triarylpyrylium salt 4. BMImPF6 catalyzes the self-aldol condensation of 1, whose cyclotrimerization gives an increased conversion to 4 at the expense of 3 normally obtained from the cyclotrimerization of 1 in common organic solvent.