乙酸肉桂酯的合成.ppt

Synthesis of cinnamyl acetate（乙酸肉桂酯）by solidliquid phase transfer catalysis:Kinetic study with a batch reactor Catalysis Communications 10(2009)16381642化学与化学工程学院化学与化学工程学院陈小玲陈小玲 .ContentsIntroduction1Experimental2Results discussion34Conclusions.1.IntroductionL-L PTCIt involves the reaction of anionic reactant from aqueous phase with the reactant in organicphase by a phasetransfer catalystS-L TPCIt involves the reaction between the solid nucleophile with the other reactant in the organic liquid phasePTC phase transfer catalysis.1.Introduction L-L PTC eliminates the need of using aqueous phase thus eliminates the separation problems and easy recovery of the catalyst enhances the productselectivity by avoiding the side reactionslower selectivityand other side reactionssynthesis of fine and specialty chemicalsseparation and purifying the final productCompared with L-L PTC and L-S PTCL-S PTCthe carboxylic acids shows less reactivityomega phase”enhance the solubilization of the solid and formationof the catalytic intermediate.1.Introduction we focus our efforts on studying the kinetics and factors affecting the synthesis of cinnamyl acetate（乙酸肉桂酯）（乙酸肉桂酯）from cinnamyl bromide（肉桂酸溴）（肉桂酸溴）and sodium acetate（乙酸钠）（乙酸钠）by SL PTC.1.Introduction .2.Experimental add chlorobenzene to 50 mL and the temperature was raised to 90C with constant stirringProductadd a requiredamount of phase transfer catalyst when the temperature reached 90C At preset times,thestirrer was turne off temporarily,0.5 ml of organic solution was pipetted outanalyzed on a gas chromatograph using SE-30 Column.3.Results discussion7 factorstype of catalystspeed of agitationreaction temperaturewater addition size of sodium acetatecatalyst loadingconcentration of reactant In order to optimize the reaction conditions,the esterification reaction was carried out by varying factors as follow:.3.Results discussion3.1 Effect of agitation speed The interfacial mass transfer resistance between the solid surface and organicphase is negligible when the agitation speed is above 600 rpm.In this context,agitation speed was fixed at 600 rpm for all furtherexperiments.3.Results discussion3.2 Effect of alkyl chain length of the catalyst Hence TBAB is chosen as the phase transfer catalyst in the following studies.3.Results discussion3.3 effect of reaction temperatureAlthough a high temperature usually favors the side reactions,no side products were found at 95 C in this study.3.Results discussion3.4 Effect of catalyst loadingSince reasonable conversions are observed at the catalyst loading of 1.6 g,the further experiments are carried out at the catalyst loading of 1.6 g.3.Results discussion3.5 Effect of mole ratioThe conversion of cinnamylbromide increased with the increase of mole ratio of cinnamyl bromide to sodium acetate from 1:1 to 1:1.5 and remained almost constant thereafter.3.Results discussion3.6 Effect of water additionThe optimal usage of water in the present study was observed to be 4 ml.3.Results discussion3.7 Effect of patical size of sodium acetateLow reactivity of the sodium acetate granules may be attributed to their low surface area and mass transfer limitations.3.Results discussion rate expression(1).3.Results discussion rate expression（2）.3.Results discussion rate expression k=kCc（3).4.Conclusions1、The solidliquid phase transfer catalysis was successfully employed for the synthesis of cinnamyl acetate from the esterification of sodium acetate with cinnamyl bromide by using TBAB as the catalyst.2、Using a moderate amount(1.6 g)of tetran-butyl ammonium bromide as the catalyst at 95 C.3、The solidliquid interfacial mass transfer resistance is negligible at agitation speed above 600 rpm.4、The catalyst with longer alkyl chain length gives better performance,however,it will more easily dissolved in the organic phase and hence is more difficult to be removed and reused after the reaction.5、Adding 18 ml of water improved the reactivity of the catalyst.6、The reaction 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