Indirect benzylation of Ferulic Acid ……… H.Osman, S.A.Hamid, M.H.Al–Douh, A.Fang-Lim Univ. Aden J. Nat. and Appl. Sci., Vol. 13 No. 2 – August 2009 259 Indirect benzylation of Ferulic Acid catalysed by TBAI Hasnah Osman,* Shafida Abd. Hamid, Mohammed Hadi Al–Douh and Antonia Fang-Lim School of Chemical Sciences, Universiti Sains Malaysia (USM), Minden 11800, Pinang, Malaysia. * E-mail: ohasnah@usm.my Abstract The protection reaction on the hydroxyl group of ferulic acid 1 has been discussed. Methylation of the carboxylic side followed by the benzylation of the hydroxyl group using tetra-n-butyl ammonium iodide (TBAI) as a catalyst afforded 4-benzyloxy-3-methoxymethyl cinnamate 3. The purified product has been characterized by 1D NMR spectroscopy. Keywords: 1D NMR, Ferulic acid, Benzylation, tetra-n-butyl ammonium iodide TBAI. Introduction Ferulic acid (4-hydroxy-3-methoxycinnamic acid) 1 is the most common phenolic acid found in the Gramineae family, which is particularly abundant in cereal grains. (6) It is mostly conjugated with mono– and oligosaccharides, polyamines, lipids and polysaccharides and also present as free acid in plants. (7) Ferulic acid, 1 obtained in food such as apple, orange and coffee is well-known as an anti-oxidant and anti-aging compound. Furthermore, is able to reduce oxidative stress and formation of thymidine dimers in skin. (5) Other than its application as an anti-oxidant, ferulic acid 1 also has a property of an anti-cancer activity. In industrial applications, 1 is widely used as a precursor for manufacturing aromatic compounds such as vanillic acid. (7) This work describes the protection reaction on the hydroxyl group of ferulic acid using indirect benzylation catalysed by TBAI. The structures of known compounds were justified by comparing the spectral data with reported values in the literature (Scheme 1).