Synthesis of methyl 12-benzoyldehydroabietate in ionic liquid

Abstract

In the presence of the ionic liquid [bmim]Br/AlCl₃ as green reaction medium, methyl 12-benzoyldehydroabietate was synthesized through Friedel-Crafts acylation reactions on the aromatic ring of methyl dehydroabietate. The optimum synthetic conditions of the target product were found to be as follows: molar ratio of methyl dehydroabietate to [bmim]Br to AlCl₃ to benzoyl chloride 1:4:8:8, reaction temperature 40°C, reaction time 2 h. The target product was analyzed and characterized by means of IR, MS, NMR and elemental analysis. The results show that this novel method has the advantages of mild condition, short reaction time and environmental benignity.

Keywords

ionic liquid / dehydroabietic acid / Friedel-Crafts acylation / methyl 12-benzoyldehydroabietate