In this paper Bisphenol AF was prepared in a new route which from HFA·3H2O and aniline in 4 steps:alkylation,diazotization,hydrolysis,Friedel-Crafts alkylation,t he total yield was 67.4%.The produces were identified by GC/MS,IR and 1H-NMR, and their reaction mechanism were discussed.The results are introduced as follows.(1)The synthesis of 2-(4-aminophenyl)-1,1,1,3,3,3-hexafluoropropan-2-ol(â… ) was studied,which catalyzed by kinds of bronsted acids,the PEG ionic liquid and Nb2O5.The result showed that compound(â… ) was obtained with 96.3%yield under optimal conditions that Nb2O5 as the catalyst,n(HFA·3H2O):n(aniline):n(Nb2O5) is 2:1:0.1,reflux condition and the reaction time is 6 h.The reaction mechanism is described as follows,because of oxygen vacancies,Nb2O5 is easy to accept the external electronics and form Lewis acid centers,which has good catalytic ability.(2)Then 2-(4-hydroxy phenyl)-1,1,1,3,3,3-hexafluoropropan-2-ol(â…¡) was synthesize d from compound(â… ) via diazotization,hydrolysis.The optimum reaction conditions were as follows:during diazotization,n(â… ):n(H2SO4):n(NaNO2) is 1:4.1:1.1,th e content of H2SO4 is 30%and reaction temperature- 2~2℃;during hydrolysis,the content of H2SO4 is 50%,n(H2SO4):n(â… ) is 11:1.Under these conditions,the yie ld was 89.4%.(3)In the presence of catalysts,the Friedel-Crafts alkylation of compound(â…¡) wh ich with phenol yielded target compound bisphenol AF(â…¢) was studied.The result s howed that methanesulfonic acid is the best catalyst,and Bisphenol AF was obtained with 78.3%yield.
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