A New Route To Synthesize Etoxazole

Etoxazole,a kind of safe and environmental-friendly novel acaricide,has outstanding performance and high activity in the prevation of mites by the way of inhibiting the the incorporation of the radiolabelled chitin precursor into the integuments of pest invertebrates,therefore,Etoxazole can alse restrain some mites free of other acaricides.Nowadays,few companies make it into industrialisation,though the patent of Etoxazole has expired.It is of great importance to study the production technology of Etoxazole,considering the change of world market and transient opportunities.In this paper,a novel and convinent approach to Etoxazole has been found on the basis of the reviews of the synthesis methods of the Etoxazole.To acquire the key intermediate 2-amino-2-(4-(tert-butyl)-2-ethoxyphenyl)ethan-1-ol,we made the starting material 3-(tert-butyl)phenol ethylation,acylation,bromination,hydrolysis and reductive amination.The final product Etoxazole was achieved by the cyclization of 2,6-difluorobenzoic acid and 2-amino-2-(4-(tert-butyl)-2-ethoxyphenyl)ethan-1-ol.What's more,some investments were made to optimize the procedure in this paper,including the raio of reaction materials,the sreen and the dosage of catalysts,the temperature and the time of reaction and the solvent screening and so on.Meanwhile every intermediates and Etoxazole were characterized by GC,HPLC,NMR and MS.Under the optimization of process condition,the result was excellent that the purity was 98.0% and the yield was 57.2%.The procedure herein has the advantages of high yield,low cost,convenient operation,easy work-up and eco-friendly synthesis,compared with others.