Naproxen And Its Intermediates In The Synthesis And Process Improvement

Naproxen is a kind of non-steroidal anti-inflammatory (NSAID) agents which is widely used today. It is a chiral molecule, and the S-naproxen is about 28 times more effective than its R-isomer. At present, the S-Naproxen is mainly produced through resolution in industry, and there are many deficiencies in it. So it is of great importance to find an economical and effective way to synthesize S-Naproxen directly.2-(l-bromoethyl)-2-(6-methoxy-2-naphtyl)-l , 3-dioxolane is one of the key intermediates in the process of synthesizing Naproxen. On the basis of former people's research , and using 2-bromo-l-(6methoxy-2-naphthyl)-propan-l-one as the start material, the 2-(l-bromoethyl)-2-(6-methoxy-2-naphtyl)-l, 3-dioxolane has been obtained through debromination, selective bromination, ketalization. The effect of the solvent's quantity, compounding ratio, the compounding ratio of auxiliary product, reaction time and reaction temperature to the product yield is mainly studied in the debrominating process; the effect of the selection of solvent and brominating agent, the compounding ratio of the auxiliary product, the solvent's quantity ect. to the product yield is mainly studied in the brominating process, and the best synthesizing process conditions is obtained; the effect of the selection, quantity of the solvent, the reaction temperature, reaction time, and the catalyzer to the product yield is researched in the process of ketalization and the relative preferable process conditions has been got. The DSC, IR, 1H~NMR and GS are used to analyze and certificate the products.