Technological Study Of Synthesizing 2-Bromo-1-(6'-Methoxy-2'-Naphthalene) Propan-1-one

Naproxen, one of the twenty top-selling products in the U.S. retail pharmaceutical market, is an optically active 2-naphthypropanoic acid. Extensive pharmacological studies show that the S-isomer of Naproxen is about 28 times more effective than the corresponding /?-isomer. In our country, S-isomer is obtained by resolution. But the method of resolution has many disadvantages. Therefore, how to synthesize directly 5-isomer Naproxen becomes the most important problem confronting many scientists.In the paper, microstructure character of 2-methoxynaphthalene and 1-bromo-2-methoxynaphthalene, which includes charge density, bond angle and space distance of atoms, was obtained by means of PM3 program. Therefore, why and how about protecting 1-position of 2-methoxynaphthalene were demonstrated and analyzed.Study on synthesis of 2-bromo-l-(6'-methoxy-2'-naphthanyl) propan-1-one, one of the key intermediates, was the main content of this thesis. The compound was synthesized, starting from 2-naphthanol, via etherification, bromination, propionyl and denomination. In the course of etherification, physical and chemical absorption were combined simultaneously in the reaction system, and effects of 4A molecular sieve on yield and other factors were studied; In the process of bromiantion, propionyl and debromination, effects of many usual parameters on yield of every target product were discussed, which include mass of solvent, proportion of substrates, reaction time and reaction temperature, etc. On the base of study above, l-(6'-methoxy-2'-naphthanyl) propan-1-one was obtained. The target compound, 2-bromo-l-(6'-methoxy-2'-Naphthanyl) propan-1-one, was synthesized by discussing the effects of choice of solvent, proportion of substrates and reaction time, etc. From the study above, the optimum conditions of synthesizing 2-bromo-l-(6'-methoxy-2'-Naphthanyl) propan-1-one were got.The results showed that this technology scheme has such advantages as short reaction time, high yield, friendly environment and without gaining byproduct, l-(2'-methoxy-l'-naphthan-yl) propan-1-one, and so on.With the aid of DSC, IR, 'H-NMR and GS, analyses of all products were accomplished.