Study on cataliytic synthesis of 2-isopropyl-1,3-benzodioxolane by phosphotungstic acid supported on activated carbon

2-Isopropyl-1,3-benzodioxolane was synthesized from catechol and isobutyric aldehyric using the phosphotungstic acid supported on activated carbon as catalyst.The effects of ratio of reactants,supported quantity and amount of catalyst and amount of dehydratiing agent were investigated by the orthogonal test.The results showed that the optimum condensation conditions are as follows:catechol:isobulyric aldehyde:catalyst:dehydrating agent is 1mol:1.5mol:10g:200mL.Supported quantity of catalyst is 23.6%,reaction temperature is reflux temperature;reaction time is about 4h.The yield can reach 90.8% under the optimum conditions and the catalyst can be used repeatedly.