Research Of Reaction Process Of Naphthalene And Hydroxylamine Salt Catalyzed By Vanadium Catalyst

1-naphthylamine and 1,5-diaminonaphthalene(NDA) are very important chemical products and organic synthesis intermediates. Especially, NDA is the key raw material of 1,5-diisocyanate(NDI). As the demand for NDI, the main raw material of polyurethane, grows quickly, research on NDA is also increasing. Traditional process for preparation of 1-naphylamine and NDA no longer meet the concept of green chemistry. On the contrary, introducing-NH2 to naphthylamine directly can improve the atomic availability, and it also can make the process more concise, clean and green. In this study, we explored the reaction of one-step oxidation-amination at the presence of catalyst or no catalyst, with naphthalene as reaction medium, hydroxylamine salt as the aminating agent and acidic solution was used as the reaction medium. Firstly, in the absence of catalysts, we studied effects of solvent and feeding method on generating 1-naphthylamine and found that mixture of glacial acetic acid and water was better reaction medium while feeding method made no difference. Then we compared different catalyst, and elected NaVO3 as the best one for the generation. Using acetic acid water solution and NaVO3, we studied the effect of acidic medium, the amount of catalyst, feed ratio, reaction temperature, reaction time on the reaction. Finally under the optimized condition: mnapHthalene:mcat=1:0.5, Vglacial acetic:acid:Vwate =3:1, nnapHthalene:nhydroxylamine =1:10, T=80℃, t=4h 1-naphthylamine’s yield can reach 3.93%.Secondly, NDA was chosen as the target product and V2O5, which was the most effective catalyst to generate NDA, was adopted. We studied effect of acidic medium, the amount of catalyst, feed ratio, reaction temperature, reaction time, finding that the best reaction condition was that mnapHthalene:mcat=1:0.4, Vglacial acetic:acid:Vwate=3:1,0.04 g of V2O5, nnapHthalene:nhydroxylamine =1:10, T=80℃, t=5h was the best conditions, under which, NDA’s yield could be up to 5.23%, while 1-naphthylamine’s yield was 1.57%.Finally, we qualitatively analyzed the productions and speculated the possible reaction mechanism.