Alkyl bromides played various important roles in chemical industry concerned with products for daily use and synthesis of medical aspects. N-octyl bromide was a very important intermediate in the synthesis of Jun-du-tsing. It was also the important materials in the synthesis of UV-531.
N-octyl bromide was synthesized by hydrobromic method in which took n-octanol and industrial waste hydrobromic acid(48%) as materials, concentrated sulfuric acid as a catalyst. The mole ratio of octanol, hydrobromide,octanol and concentrated sulfuric acid were observed, as well as the impact of time on reaction rate. The best synthetic conditions of the experiment was as follows: octanol﹕hydro- bromide﹕concentrated sulfuric acid (mole Ratio) 1:1.15:1.38, reaction temperature 110 ℃ ~115 ℃, reaction time 3h. The yield of the product was more than 99%.
Raw product was analyzed by GC and IR for purity analysis and structure characterization. The result showed that the purity of the product was 99%, and also showed that no by-product was generated. IR indicated that the spectrum of the product was the same as the standards.
Compared with classical methods, this method has the advantages of good material feeding ratio, short reaction time, easy preparation and mild reaction conditions, yield and purity reached to 99.0%. The product can be directly used for produce UV-531 without purification. That shows it has a good industrial prospect. It can provide reliable reference for the green synthesis of UV-531
Key words:n-octyl bromide ,UV-absorber UV-531,Law Hydro bromide 2-Hydroxy-4-octyloxybenzophenone