N,N-Dimethylation of Nitro-eugenol to its New 4-Allyl-2-(dimethylamino)-6-methoxyphenol via Eschweiler–Clarke Methylation Reaction

Abstract

Eugenol is a main constituent of essential oil and can be extracted and isolated from clove (Syzygium aromaticum). Eugenol has widely biological activities such as antiseptic and anesthetic. Eugenol can be used as a fine chemical for further synthesis of new or novel compounds. The main aim of this research was to develop new or novel compounds with potential biological activity such as 4-allyl-2-(dimethylamino)-6-methoxyphenol from eugenol (1). Derivatization of eugenol to its nitro derivative (2) can be achieved by treated with ammonium nitrate and potassium bisulphate. One-pot synthesis method via the Eschweiler–Clarke methylation of nitroeugenol using formaldehyde, formic acid, Zn catalyst, gave the N,N-dimethylation of nitro moiety. The result was then analyzed by GC-MS and NMR. The GC-MS analyses showed peak with m/z of 207 (59.51 %) and consistent with the molecular formula C₁₂H₁₇O₂N. The ¹H NMR was in accordance with the proposed structure which showed 17 protons corresponded to 4-allyl-2-(dimethylamino)-6-methoxyphenol (3).