Study On The Synthesis Of 4-(4-hydroxyphenyl)-2-butanone By Anise Aldehyde

4-?4-Hydroxyphenyl?-2-butanone is a familiar fruit smell spice,which can be widely used in food,and also be used in synthesis of pharmaceuticals,dyes and agricultural insect attractant.Natural 4-?4-hydroxyphenyl?-2-butanone exists in fruits such as raspberry,grapes and pinus yunnanensis needles.Because of the concentration of it in above plants is about 0.115 mg/kg,4-?4-hydroxyphenyl?-2-butanone used in our life is mostly synthesized by chemical method.The traditional synthesis process of 4-?4-hydroxyphenyl?-2-butanone usually take petrochemical products as raw materials.The synthesis process of 4-?4-hydroxyphenyl?-2-butanone always catalyzed by inorganic acid or alkali,which always come along with the problem of equipment corrosion,environmental pollution and many side reactions.The quality of product is poor.In this thesis,natural anisic aldehyde was taken as raw material,and 4-?4-hydroxyphenyl?-2-butanone was sythesized through three steps: Claisen-Schmidt condensation,transfer hydrogenation and demethylation.We studied the catalytic system of the three steps.At the same time,the reaction conditions were optimized by us.This synthetic route is a green synthesis process.The results show very good prospects for industrial application.Firstly,Anisic aldehyde and acetone were used to synthesize 4-?4-methoxyphenyl?-3-buten-2-one through Claisen-Schmidt condensation reaction.Hydrotalcite is selected to be catalyst after comparation of different solid alkali.On the basis of it,we studied the effects of n?NaOH?:n?Na2CO3?,ultrasonic treatment and other relevant factors on the activity of hydrotalcite.The results show that n?Mg?NO3?2?:n?Na2CO3?:n?NaOH?=1:2:2,ultrasonic treatment through the coprecipitation,calcinate at 450? were the best experimental conditions to synthesis hydrotalcite.The results of experiments showed that the optimal reaction conditions were: reaction time 10 h,the reaction temperature was 60?,the amount of catalyst was 6% of anisic aldehyde,n?acetone?:n?anisic aldehyde?=9:1.Under these conditions,the average conversion of anisic aldehyde was 99.6%,the average yield of 4-?4-methoxyphenyl?-3-buten-2-one is 98.7%.Catalyst still has good catalytic activity after used three times.Secondly,4-?4-methoxyphenyl?-3-buten-2-one and HEH were used to synthesize anisyl acetone through hydrogen transfer reaction,in which HEH was the hydrogen source.The effects of solvent species,catalyst species,reaction temperature,reaction time,catalyst amount and other factors on the yield of anisyl acetone were studied.The optimum reaction conditions for the synthesis of 4-?4-methoxy phenyl?-3-butene-2-ketone were determined by experiments: CH2Cl2 as solvent,temperature of the reaction was 50 ?,reaction time 5 h,n?TiCl4?:n?4-?4-methoxyphenyl?-3-buten-2-one?:n?HEH?=0.3:1.0:1.6.Under these conditions,the average yield of anisyl acetone was 98.7%.Thirdly,anisyl acetone was used to synthesize 4-?4-hydroxyphenyl?-2-butanone and 1-Dodecanethiol-NaOH was used as catalyst.The effects of reaction temperature,reaction time,catalyst amount and other factors on the yield of 4-?4-hydroxyphenyl?-2-butanone were studied.The experiment results showed that the optimum reaction conditions were: reaction temperature was 160?,reaction time 3 h,n?anisyl acetone?:n?Dodecanethiol?: n?NaOH?= 1:1.5:3.Under these conditions,the average yield of 4-?4-hydroxyphenyl?-2-butanone was 80.6%.Lastly,anisyl acetone was used to synthesis 4-?4-hydroxyphenyl?-2-butanone and Lewis acid-Na I was used as catalyst.The effects of Lewis acid species,solvent species,reaction temperature,reaction time,catalyst amount and other factors on the yield of anisyl acetone were studied.The experiment results show that the optimum reaction conditions were: CH3 CN as solvent,the course of reaction temperature was 120?,the reaction time was 11 h,n?anisyl acetone?:n?Na I?:n?AlCl₃?=1:2.5:3.Under these conditions,the average yield of 4-?4-hydroxyphenyl?-2-butanone was 97.0%.The products were analyzed by FT-IR,¹HNMR,GC,GC-MS,and catalysts were analyzed by SEM,FT-IR,XRD,BET,respectively.