由_环柠檬醛直接缩合制备_紫罗兰酮的研究.docx

文章编号：1003-9015(2011)03-0538-05由α-环柠檬醛直接缩合制备β-紫罗兰酮的研究沈润溥1,胡四平2,宋小华3,陈建辉3,孙雄生3,虞国棋2,吴春雷1(1.绍兴文理学院,浙江绍兴312000;2.浙江医药股份有限公司维生素厂,浙江绍兴312000;3.浙江医药股份有限公司新昌制药厂,浙江新昌312500)摘要：以柠檬醛为原料经酸化环化得到α-环柠檬醛，然后直接与丙酮缩合得到产物β-紫罗兰酮。对影响反应的主要因素包括催化剂NaOH溶液浓度、反应温度和时间等进行了优化，得到如下较佳工艺条件：α-环柠檬醛和丙酮在5%的NaOH水溶液作用下于45℃反应6h，减压精馏得到产物β-紫罗兰酮，收率为71.6%，含量为93.5%(GC)。得到的含有α-环柠檬醛、β-环柠檬醛及α-紫罗兰酮的前馏分可以回收套用。本工艺反应机理为在碱催化下缩合反应通过两种途径同时进行，一是α-环柠檬醛先重排成β-环柠檬醛再与丙酮缩合，另一种是α-环柠檬醛先与丙酮缩合成α-紫罗兰酮，再重排得目标产物β-紫罗兰酮。与已有工艺相比，本路线采用了α-环柠檬醛为原料，且步骤简洁、收率良好，对探索合成β-紫罗兰酮的有工业意义的路线具有重要指导作用。关键词：β-紫罗兰酮；α-环柠檬醛；α-紫罗兰酮；β-环柠檬醛；缩合；双键移位中图分类号：O621.3；O631.5文献标识码：ASynthesisofβ-Iononefromα-CyclocitralDirectlybyCondensationReactionSHENRun-pu1,HUSi-ping2,SONGXiao-hua3,CHENJian-hui3,SUNXiong-sheng3,YUGuo-qi2,WUChun-lei1(1.ShaoxingUniversity,Shaoxing312000,China;2.VitaminFactory,ZhejiangMedicineCo.Ltd.,Shaoxing312000,China;3.XinchangPharmaceuticalFactory,ZhejiangMedicineCo.Ltd.,Xinchang312500,China)Abstract:β-Iononewassynthesizedbycondensationreactionofacetoneandα-cyclocitralwhichwaspreparedfromcitralthroughcyclization.Theeffectsofmainfactors,suchasthereactiontemperature,reactiontimeandtheconcentrationofNaOHsolutionwhichisusedascatalyst,onthecondensationreactionwereinvestigated.Theoptimumreactionconditionsfoundareasfollows:5%NaOHaqueoussolutionascatalyst,reactiontemperatureof45℃andreactiontimeof6h;Underaboveconditions,theβ-iononeyieldcanbe71.6%withthepurityof93.5%(GC).Theoverheaddistillateincludingunreactedα-cyclocitralandbyproductsα-iononeandβ-cyclocitralcanbereusedasrawmaterialswithoutanyreprocessing.Themechanismofthecondensationreactionofα-cyclocitralwithacetonewasstudied,theconclusionwasthatthereactionmayproceedwithtwowaysatthesametime:oneisthattheβ-cyclocitralfromtherearrangementofα-cyclocitralcondenseswithacetonetoformtheβ-ionone,theotheristhattheα-iononefromthecondensationofα-cyclocitralandacetoneisrearrangedtoformtheβ-ionone.Comparingwiththeexistingβ-iononesynthesisrouteofusingpseudoiononeorβ-cyclocitralasrawmaterial,thenewβ-iononesynthesisroutepropos