Chemistry Department 01 包江胤 郑睿 Rearrange reactions Chemistry Department 01 包江胤 郑睿

1.Abstract The history is as long as organic compounds Definition: a reaction that results in a product with a different carbon skeleton from the reactant

Classification Nucleophilic rearrangments Free radical rearrangments Electrophilic rearrangments Pericyclic reaction

Nucleophilic rearrangements

Eletrons on the molecular orbitals of the transition state & reactive intermidiate

2.Nucleophilic rearrangements General rule 1)Process 2)Condition 3)Migrating group 4)Stereochemistry 5)Memory effect

1)Process

Classification 1)Carbonium ion 2)Carbonyl 3)Carbene 4)Electron-defect nitrogen 5)Electron-defect oxygen 6)Aromatic series

1)Carbonium ion (1)Rearrangements in the composition of aldehydes and ketones (2)Rearrangements of pinacols (3)Wagner-Meerwein’s rearrangements (4)Demyanov’s rearrangements (5)Tiffeneau-Demyanov’s circles expanding (6)Rearrangements from dienones to phenols (7)Rearrangements with allyl groups

Rearrangements in the composition of aldehydes and ketones

33-36% O.S.Ⅳ，225

Rearrangements of pinacols

2)Carbonyl Benzil-benzilic acid rearrangements (2)Rearrangements of aldehydes or ketones when catalysised by acid

Benzil-Benzilic acid arrangement

3)Carbene Arndt-fistert synthesis and Wolff rearrangement (2)Other carbenes’s rearrangement reaction

4)Electron-defect nitrogen (1)Beckmann’s rearrangement (2)Hofmann’s rearrangement (3)Curtius’s rearrangement (4)Schmidt’s rearrangement (5)Neber’s rearrangement (6)Lossen’s rearrangement

Beckmann’s rearrangement

Hofmann’s rearrangement

Curtius’s rearrangement

Schmidt’s rearrangement

Neber’s rearrangement

5)Electron-defect oxygen (1)Hydroperoxide rearrangement (2)Baeyer-Villiger rearrangement

6)Aromatic series (1)Bamberger rearrangement (2)Scommelet-hauser rearrangement (3)Simles rearrangement

3.Free radical rearrangements 1,2 shift Others (1)Barton rearrangement (2)Hofmann-Loffler-Freytag rearrangement

Barton’s rearrangement

4.Electrophilic rearrangements 1) Aliphatic rearrangements (1)Farorskii rearrangements (2)Grovenatein-Zimmerman rearrangements (3)Stevens rearrangements (4)Wittig rearrangements

2)Aromatic series (1)Fries rearrangement (2)Aromatic ether rearrangement (3)Orton rearrangement (4)N-nitro aromatic amine rearrangement (5)Fischer-Hepp rearrangement (6)Hofmann-Martius rearrangement (7)Diazonamino compounds rearrangement

Favorskii’s rearrangements

Fries’ rearrangements

5. Pericyclic reaction (1)Electrocyclic reaction (2)σ-bonds shift (3)Cope rearrangements (4)Claisen rearrangements (5)Fischer indole synthesis (6)Benzdine rearrangements

Electrocyclic reaction

References 杜汝励，分子重排反应，人民教育出版社，1981年 王其华，有机反应机制导论，高等教育出版社，1991年 李进文，范如霖编译，实用有机化学手册，上海科学技术出版社，1981年 金寄春，重排反应，高等教育出版社，1990 P.Sykes,A Guidebook To Mechanism In Organic Chemistry,Longman,1981