单击此处编辑母版标题样式,,单击此处编辑母版文本样式,,第二级,,第三级,,第四级,,第五级,,,精选版课件ppt,*,Chapter 5,Rearrangement Reaction,第五章 重排反应,,1,,精选版课件ppt,,重排反应,,,,1.,碳原子到碳原子重排,,（,1,）,Wagner-Meerwein,重排,,（,2,）,Pinacol,重排,,（,3,）二苯乙醇酸重排,,（,4,）,Favorski,重排,,（,5,）,Wolff,重排及,Aendt-Eistert,反应,,,,,2,,精选版课件ppt,,重排反应,,,2.,碳原子到杂原子重排,,,（,1,）,Beckmann,重排,,（,2,）,Hoffman,重排,,（,3,）,Curtius,重排,,（,4,）,Schmidt,重排,,（,5,）,Bayer-Villiger,反应,,,3,,精选版课件ppt,,重排反应,,,3.,杂原子到碳原子重排,,（,1,）,Stevens,重排,,（,2,）,Sommelet-Hauser,重排,,（,3,）,Wittig,重排,,4.,s,键迁移重排,,,（,1,）,Claisen,重排,,,（,2,）,Cope,重排,,（,3,）,Fischer,吲哚合成,4,,精选版课件ppt,,分子重排反应,,分子重排反应就是化学键的断裂和形成发生在同一分子中，引起组成分子的原子的配置方式发生改变，从而形成组成相同、结构不同的新分子的反应。
重排反应中键的断裂和形成的方式有异裂、均裂和环状过渡态三种5,,精选版课件ppt,Radical rearrangement,Usually, the rearrangement was classified by the electron property of the moving group,Nucleophilic rearrangement,Electrophilic rearrangement,第一节 重排反应机理,6,,精选版课件ppt,,2024/10/31,1. Nucleophilic rearrangement,,7,,精选版课件ppt,,2024/10/31,2. Electrophilic rearrangement,8,,精选版课件ppt,,2024/10/31,3. Radical rearrangement,9,,精选版课件ppt,1.,反应通式,第一节,,碳原子到碳原子重排,一、,Wagner-Meerwein,重排,10,,精选版课件ppt,11,,精选版课件ppt,2.,反应机理,12,,精选版课件ppt,3.,影响因素,,（,1,）碳正离子形成方式：卤代烃与,Lewis,酸作用、醇与酸作用、烯烃质子化、胺与亚硝酸作用。
2,）,the stereochemistry of the migrating group is retained, which is in accordance of the,Woodward-Hofmann rules.,13,,精选版课件ppt,4.,应用特点,,（,1,）醇类的,Wagner-Meerwein,重排,,2024/10/31,Addition of a nucleophile,Loss of a proton,,More stable,14,,精选版课件ppt,,2024/10/31,15,,精选版课件ppt,（,2,）卤代烃的,Wagner-Meerwein,重排,Stable cation,,16,,精选版课件ppt,,2024/10/31,Stable cation,,Migratory order of the migration groups,17,,精选版课件ppt,（,3,）胺类化合物的,Wagner-Meerwein,重排,,2024/10/31,18,,精选版课件ppt,,2024/10/31,19,,精选版课件ppt,二、,Pinacol Rearrangement,1.,反应通式,20,,精选版课件ppt,X = Cl, Br, I, SR, OTs, OMs, N2,+,21,,精选版课件ppt,2.,反应机理,22,,精选版课件ppt,（,1,）碳正离子的稳定性,,the product is usually formed,via the most stable,carbocation intermediate when the glycol substrate is unsymmetrical;,,,3.,影响因素,23,,精选版课件ppt,（,2,）立体化学因素,24,,精选版课件ppt,（,3,）迁移能力及推广的重排,H>Ph>3º>2º>1º,,,,25,,精选版课件ppt,,26,,精选版课件ppt,27,,精选版课件ppt,,α,-,二酮在浓碱作用下发生重排，生成安息香酸的重排反应称为二苯乙醇酸重排。
三、二苯乙醇酸重排,1.,反应通式,28,,精选版课件ppt,2.,反应机理,29,,精选版课件ppt,3.,影响因素,（,1,）用苛性碱得到羟基酸，用醇盐则生成酯；,30,,精选版课件ppt,（,2,）环状二酮生成环状羟基酸,31,,精选版课件ppt,四、,Favorski,重排,1.,反应通式,32,,精选版课件ppt,2.,反应机理,33,,精选版课件ppt,催化剂的影响,3.,影响因素,34,,精选版课件ppt,由卤代酮制备羧酸衍生物,4.,应用特点,35,,精选版课件ppt,五、,Wolff,重排及,Arndt-Eistert,反应,Wolff rearrangement,1.,反应通式,36,,精选版课件ppt,2.,反应机理,37,,精选版课件ppt,38,,精选版课件ppt,(1) the reaction can be initiated thermally, photolytically, or by transition metal catalysis;,,(2) freshly prepared silver(I)oxide or silver(I)benzoate are best suited for the reaction;,,(3) if the migrating group has a stereocenter, the stereochemistry remains unchanged (net retention of configuration) after the migration;,,,,3.,影响因素,39,,精选版课件ppt,Examples,40,,精选版课件ppt,Arndt-Eistert synthesis,1.,反应通式,41,,精选版课件ppt,2.,反应机理,42,,精选版课件ppt,羧酸同系化,C+1,3.,应用特点,43,,精选版课件ppt,44,,精选版课件ppt,酮肟在酸性催化剂的作用下重排成酰胺的反应称为贝克曼重排。
H,+,R´-C-NHR,O,=,,第三节,,碳原子到杂原子重排,一、,Beckmann,重排,1.,反应通式,45,,精选版课件ppt,重排,互变异构,2.,反应机理,46,,精选版课件ppt,（,1,）催化剂影响,,H,2,SO4, HCl/Ac,2,O/AcOH, etc.,,PPA,、,POCl3,、,PCl5,、,SOCl2,、,MsCl,、,TsCl,等3.,影响因素,47,,精选版课件ppt,（,2,）溶剂的影响,,用极性小或非极性的非质子溶剂，,PCl5,催化可防止异构化,48,,精选版课件ppt,当溶剂中含有亲核性化合物、分子内含有亲核性官能团、溶剂本身为亲核性化合物，碳正离子与其结合而得不到酰胺,,,,,,,也可用此制备苯并咪唑衍生物,49,,精选版课件ppt,立体专一性,4.,应用特点,50,,精选版课件ppt,二、,Hofmann,重排,1.,反应通式,51,,精选版课件ppt,2.,反应机理,52,,精选版课件ppt,53,,精选版课件ppt,3.,应用特点,（,1,）制备,C-1,伯胺,54,,精选版课件ppt,(2),因亲核剂不同而产物各异,55,,精选版课件ppt,,（,3,）,,Curtius Rearrangement,56,,精选版课件ppt,57,,精选版课件ppt,58,,精选版课件ppt,Example,59,,精选版课件ppt,60,,精选版课件ppt,（,4,）,,Schmidt Rearrangement,61,,精选版课件ppt,62,,精选版课件ppt,63,,精选版课件ppt,64,,精选版课件ppt,（,5,）,,Lossen Rearrangement,65,,精选版课件ppt,66,,精选版课件ppt,Example,67,,精选版课件ppt,,酮类化合物被过酸氧化，与羰基直接相连的碳链断裂，插入一个氧形成酯的反应称为拜耳,-,魏立格（,Baeyer-Villiger),氧化重排。
CH,3,CO,OOH,CH,3,COOC,2,H,5,40,o,C,+ CH,3,CO,OH,常用的过酸有：,,（,1,）一般过酸,+,无机强酸（,H,2,SO,4,）,,（,2,）强酸的过酸 ：,CF,3,COOOH,,（,3,）一般酸,+,一定浓度的过氧化氢（产生的过酸立即反应）,（,5,）拜耳,-,魏立格氧化重排,,,,,68,,精选版课件ppt,反应机理,H,+,O-O,键断裂,-R´´COO,- ,,-H,+,R´,重排,R,3,C- > R,2,CH- ,,>RCH,2,- > CH,3,-,>,>,,,,,69,,精选版课件ppt,3.,从杂原子到碳原子的重排,Stevens,重排,70,,精选版课件ppt,R1 = EWG = Ar, heteroaryl, COR, COOR, CN;,,Y= CH,2,, CHR, NH;,base: NaH, KH, RLi, ArLi, RONa, ROK,R4 = CH3, alkyl, allyl, benzyl,CH2COAr,71,,精选版课件ppt,72,,精选版课件ppt,73,,精选版课件ppt,Example,74,,精选版课件ppt,75,,精选版课件ppt,Sommelet-Hauser,重排,,76,,精选版课件ppt,77,,精选版课件ppt,Wittig,重排,78,,精选版课件ppt,Example,79,,精选版课件ppt,80,,精选版课件ppt,4.,s-,键迁移重排,Claisen,重排,（,1,）,Claisen Rearrange,81,,精选版课件ppt,82,,精选版课件ppt,环状过渡态,烯丙基苯基醚,邻烯丙基苯酚,对烯丙基苯酚,互变异构,互变异构,环状过渡态,[3,3],,迁移,,,,,,,,,,,,,,,,,,,,,,,,,,[3,3],,迁移,83,,精选版课件ppt,84,,精选版课件ppt,Example,85,,精选版课件ppt,（,2,）,Amino-Claisen Rearrangement,,This reaction occurs best when nitrogen is converted to the ammonium salt.,86,,精选版课件ppt,(3) Thio-Claisen Rearrangement,,This reaction is often run with a reagent that will convert sulfur to oxygen following the reaction. An advantage of the thio-Claisen rearrangement is that the precursor can be deprotonated and alkylated.,,,87,,精选版课件ppt,88,,精选版课件ppt,(4) The Carroll Reaction,,89,,精选版课件ppt,Johnson-Claisen,重排,90,,精选版课件ppt,Mechanism,91,,精选版课件ppt,Example,92,,精选版课件ppt,Eschenmoser-Claisen,重排,93,,精选版课件ppt,Ireland-Claisen,重排,The most useful of all Claisen rearrangements. The enolate may be trapped with TMSCl or the enolate may be used directly.,The reaction works well with the free enolate and actually allows for a faster rearrangement that will occur at 25 °C (anion accelerated).,94,,精选版课件ppt,95,,精选版课件ppt,Cope,重排,96,,精选版课件ppt,97,,精选版课件ppt,Fischer indole synthesis,98,,精选版课件ppt,99,,精选版课件ppt,Mechanism,100,,精选版课件ppt,Example,101,,精选版课件ppt,。