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1、(三).烯胺的烃化反应1963年,G.Stork使用醛和叔丁基胺形成烯胺sichiff碱p-TsOH,甲苯带水(DeanandStarkapparatus),或用无水K2CO3除水优点(1)不需要碱或其他催化剂,减少羰基的自身缩合(2)可以制备单烷基化产物(3)对于不对称的酮,取代发生在取代基较少的位置烯胺的Michael反应:取代基少的位置酮的Michael反应:取代基较多的位置6-甲氧基-1-甲基-2-四氢萘酮的制备:1.烯胺的制备N2,17.6g(0.1mol)6-甲氧基-2-四氢萘酮10.6g(0.15mol)四氢吡咯(除水)300mL苯,回流分水(约2mL)减压蒸去溶剂,用
2、正己烷重结晶得无色晶体(空气中存放1-2天)。6-甲氧基-1-甲基-2-四氢萘酮的制备:2.烯胺的反应N2,18.6g(0.08mol)2-四氢吡咯基-1,3-二氢-6-甲氧基萘30mLCH3I75mL1,4-二噁烷(除水),回流18h加35mL水和1.5mL乙酸,回流5h.减压蒸去溶剂,加200mL水,乙醚萃取,干燥,蒸去溶剂,减压蒸出6-甲氧基-1-甲基-2-四氢萘酮(113-115oC)。(81%)在有支链的一侧,烯醇负离子稳定。酰基化:可在碳上酰基化,并用于增长碳链合成昆虫激素的中间体-ω-乙酰基己酸三、麦克尔Michael反应(一)概述碱性条件,活泼亚甲基化合物与a,b-不
3、饱和羰基化合物发生1,4-加成反应-SO2Ph,-1.(Michael受体)a,b-不饱和羰基化合物,a,b-不饱和腈等A:-CHO,-COR,-COOR,-COAr,-CONR2,-NO2,–CN,-SO2Ph,-SOPh2.亲核试剂:活泼甲基和亚甲基化合物乙酰乙酸乙酯丙二酸酯乙酰丙酮b-酮酸酯醛酮腈硝基化合物3.碱:醇钠、氨、胺4.溶剂:苯类、醇类、二氧六环通式:(二)应用1.制备1,5双官能团化合物2.Robinson环化A.2-Methyl-2-(3-oxobutyl)-1,3-cyclopentanedione.A1.0-L,three-necked,round-botto
4、medflaskequippedwithacondenser,magneticstirringbar,andthermometerischargedwith112.1g(1.0mol)of2-methyl-1,3-cyclopentanedione230mLofdeionizedwater,3.0mLofglacialaceticacid,and140mL(120.96g,1.72mol)ofmethylvinylketone.Thesystemisshieldedfromlightwithaluminumfoilandplacedunderaslightpositivepressu
5、reofnitrogen.Theflaskisplacedinanoilbathandthetemperatureisraisedto70°C.Thereactionismonitoredbygaschromatography(GLC)untilcomplete(1–2hr).Themixtureiscooled,transferredtoaseparatoryfunnel,andextractedwith500mLandthentwo100-mlportionsofdichloromethane.Thecombinedextractsarewashedwith500and100mL
6、ofsaturatedbrine.Thecombinedbrinewashisextractedwithafurthertwo100-mLportionsofdichloromethane.Thetotaldichloromethaneextractisdriedoversodiumsulfateandfiltered.Thesolventisremovedonarotaryevaporatorat45°C(70mm).Dryingontherotaryevaporatorat40–45°C(0.03mm)for16hrgives181.8g(100%)ofthedesiredtri
7、ketoneasanorangeoil.B.(+)-(3aS,7aS)-2,3,3a,4,7,7a-Hexahydro-3a-hydroxy-7a-methyl-1H-indene-1,5(6H)-dione.A500-mL,three-necked,round-bottomedflaskequippedwithamagneticstirringbarandanitrogeninletischargedwith188mLofN,N-dimethyl-for