Asymmetric Synthesis of Modafinil and its Derivatives by using the Functionalized Silica-based Mesoporous MCM-41

Abstract

Modafinil [2-[(diphenylmethyl)sulfinyl]acetamide] is used clinically in the treatment of narcolepsy and sleeping disorders. The synthesis of modafinil, begins with the reaction of benzhydrol and thioglycolic acid in trifluoroacetic acid to afford benzhydrylsulfinyl acetic acid. The reaction of acid with thionyl chloride in benzene followed by treatment with ammonium hydroxide gave acetamide. Synthesis of novel heterogeneous chiral catalyst by a simple and efficient method has been reported. The first, a new derivative of chiral ligand (containing amine group) in 6 steps from a cheap and readily available substrate (4-aminobenzoic acid) were synthesized in good yield. Then, this chiral ligand immobilized on silica-based mesoporous MCM-41 through its amine group. The obtained catalysts were characterized with FT-IR, XRD, BET, SEM, IR, 1H NMR,13C NMR and mass spectral and used for the first time in oxidation of benzhydrylsulfinyl acetic acid and its derivatives. The reaction using this catalysts exhibits very good yield.