摘要
A new environmental friendly catalyst,HaSiWrMo6O40/PAn was prepared and identified by means of FT-IR,XRD and TG/DTA.The optimum conditions have been found,that was,mass ratio of m(PAn):m(HaSiW6Mo6On.)was 1:1.25,volume of methanol was 20 mL,and the reflux reaction time was 2h.The structural identity of Keggin units was preserved after the incorporation into polyaniline matrix.H4SiW6Mo6040/PAn was used as catalyst in catalytic synthesis of acetals and ketals.Effects of n(aldehyde(ketone)):n(glycol),catalyst dosage and reaction time on yield were investingated.Optimal conditions were:n(aldehyde(ketone)):n(glycol)=1.0:1.5;mass fraction of catalyst to reactants,0.5%;reaction time,1.0 h and cyclohexane as water-stripped reagent,15 mL.Under these conditions,yields of actels and ketals were 31.9%-91.6%.
