Claisen rearrangement

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The Claisen rearrangement (not to be confused with the Claisen condensation) is a powerful carbon–carbon bond-forming chemical reaction discovered by Rainer Ludwig Claisen. The heating of an allyl vinyl ether will initiate a [3,3]-sigmatropic rearrangement to give a γ,δ-unsaturated carbonyl.

The Claisen rearrangement

Discovered in 1912, the Claisen rearrangement is the first recorded example of a [3,3]-sigmatropic rearrangement.[1][2][3]

Many reviews have been written.[4][5][6][7]

Mechanism[edit]

The Claisen rearrangement is an exothermic (about 84 kJ mol−1), concerted pericyclic reaction which according to the Woodward–Hoffmann rules shows a suprafacial reaction pathway. Crossover experiments eliminate the possibility of the rearrangement occurring via an intermolecular reaction mechanism and are consistent with an intramolecular process, now understood as a [3,3]-electrocyclic reaction.[8][9]

There are substantial solvent effects in the Claisen reactions. More polar solvents tend to accelerate the reaction to a greater extent. Hydrogen-bonding solvents gave the highest rate constants. For example, ethanol/water solvent mixtures give rate constants 10-fold higher than sulfolane.[1][2]

Trivalent organoaluminium reagents, such as trimethylaluminium, have been shown to accelerate this reaction.[10][11]

Variations[edit]

Aromatic Claisen rearrangement[edit]

The aromatic variation of the Claisen rearrangement is the [3,3]-sigmatropic rearrangement of an allyl phenyl ether to an intermediate which quickly tautomerizes to an ortho-substituted phenol.

The Claisen rearrangement

Meta-substitution affects the regioselectivity of the ortho rearrangement.[12][13] With the meta constituent in the 3rd position, electron withdrawing functional groups, such as bromide, move the side-chain to the right of the ether (71% of products) while electron donating groups, such as methoxy, shift it to the left (69% of products).

If ortho-position is substituted then reaction goes to para position with retention in configuration.[14]

Aromatic Claisen with ortho-position substituted

Additionally if an aldehyde or carboxylic acid occupies the substituted position the allyl side-chain displaces the group, releasing it quantitatively as carbon dioxide.[15][16]

Bellus–Claisen rearrangement[edit]

The Bellus–Claisen rearrangement is the reaction of allylic ethers, amines, and thioethers with ketenes to give γ,δ-unsaturated esters, amides, and thioesters.[17][18][19]

The Bellus–Claisen rearrangement

Eschenmoser–Claisen rearrangement[edit]

The Eschenmoser–Claisen rearrangement proceeds from an allylic alcohol to a γ,δ-unsaturated amide, and was developed by Albert Eschenmoser in 1964.[20][21]

The Eschenmoser-Claisen rearrangement

Mechanism:[14]

Eschenmoser–Claisen mechanism

Ireland–Claisen rearrangement[edit]

The Ireland–Claisen rearrangement is the reaction of an allylic acetate with strong base (such as Lithium diisopropylamide) to give a γ,δ-unsaturated carboxylic acid.[22][23][24] The actual rearrangement occurs from the enolate of the ester—this is the structural analog of the simple alkene in the original Claisen rearrangement.

The Ireland–Claisen rearrangement

Mechanism:[14]

Ireland Enolate Claisen Mechanism

Johnson–Claisen rearrangement[edit]

The Johnson–Claisen rearrangement is the reaction of an allylic alcohol with an orthoester containing a deprotonatable alpha carbon (e.g. triethyl orthoacetate) to give an γ,δ-unsaturated ester.[25]

The Johnson–Claisen rearrangement

Mechanism:[14]

Johnson–Claisen mechanism

Photo-Claisen rearrangement[edit]

The photo-Claisen rearrangement is closely related to the photo-Fries rearrangement, proceeding by a similar mechanism. Aryl ethers undergo the photo-Claisen, while the photo-Fries is experiences by aryl esters.[26]

Hetero-Claisens[edit]

Aza–Claisen[edit]

An iminium can serve as one of the pi-bonded moieties in the rearrangement.[27]

An example of the Aza–Claisen rearrangement

Chromium oxidation[edit]

Chromium can oxidize allylic alcohols to alpha-beta unsaturated ketones on the opposite side of the unsaturated bond from the alcohol. This is via a concerted hetero-Claisen reaction, although there are mechanistic differences since the chromium atom has access to d- shell orbitals which allow the reaction under a less constrained set of geometries.[28][29]

ClaisenOx.png

Chen–Mapp reaction[edit]

The Chen–Mapp reaction also known as the [3,3]-Phosphorimidate Rearrangement or Staudinger–Claisen Reaction installs a phosphite in the place of an alcohol and takes advantage of the Staudinger reduction to convert this to an imine. The subsequent Claisen is driven by the fact that a P=O double bond is more energetically favorable than a P=N double bond.[30]

The Mapp reaction

Overman rearrangement[edit]

Main article: Overman rearrangement

The Overman rearrangement (named after Larry Overman) is a Claisen rearrangement of allylic trichloroacetimidates to allylic trichloroacetamides.[31][32][33]

The Overman rearrangement

Overman rearrangement is applicable to synthesis of vicinol diamino comp from 1,2 vicinal allylic diol.

Zwitterionic Claisen rearrangement[edit]

Unlike typical Claisen rearrangements which require heating, zwitterionic Claisen rearrangements take place at or below room temperature. The acyl ammonium ions are highly selective for Z-enolates under mild conditions.[34][35]

The zwitterionic Claisen rearrangement

Claisen rearrangement in nature[edit]

The enzyme Chorismate mutase (EC 5.4.99.5) catalyzes the Claisen rearrangement of chorismate ion to prephenate ion, a key intermediate in the shikimic acid pathway (the biosynthetic pathway towards the synthesis of phenylalanine and tyrosine).[36]

Chorismate mutase catalyzes a Claisen rearrangement

References[edit]

  1. ^ a b Claisen, L. (1912). "Über Umlagerung von Phenol-allyläthern inC-Allyl-phenole". Chemische Berichte 45 (3): 3157. doi:10.1002/cber.19120450348. 
  2. ^ a b Claisen, L.; Tietze, E. (1925). "Über den Mechanismus der Umlagerung der Phenol-allyläther". Chemische Berichte 58 (2): 275. doi:10.1002/cber.19250580207. 
  3. ^ Claisen, L.; Tietze, E. (1926). "Über den Mechanismus der Umlagerung der Phenol-allyläther. (2. Mitteilung)". Chemische Berichte 59 (9): 2344. doi:10.1002/cber.19260590927. 
  4. ^ Hiersemann, M.; Nubbemeyer, U. (2007) The Claisen Rearrangement. Wiley-VCH. ISBN 3-527-30825-3
  5. ^ Rhoads, S. J.; Raulins, N. R. (1975). "The Claisen and Cope Rearrangements". Org. React. 22: 1–252. doi:10.1002/0471264180.or022.01. ISBN 0471264180. 
  6. ^ Ziegler, F. E. (1988). "The thermal, aliphatic Claisen rearrangement". Chem. Rev. 88 (8): 1423–1452. doi:10.1021/cr00090a001. 
  7. ^ Wipf, P. (1991). "Claisen Rearrangements". Comp. Org. Syn. 5: 827–873. doi:10.1016/B978-0-08-052349-1.00140-2. ISBN 978-0-08-052349-1. 
  8. ^ Hurd, C. D.; Schmerling, L. (1937). "Observations on the Rearrangement of Allyl Aryl Ethers". J. Am. Chem. Soc. 59: 107. doi:10.1021/ja01280a024. 
  9. ^ Francis A. Carey; Richard J. Sundberg (2007). Advanced Organic Chemistry: Part A: Structure and Mechanisms. Springer. pp. 934–935. ISBN 978-0-387-44897-8. 
  10. ^ Goering, H. L.; Jacobson, R. R. (1958). "A Kinetic Study of the ortho-Claisen Rearrangement1". J. Am. Chem. Soc. 80 (13): 3277. doi:10.1021/ja01546a024. 
  11. ^ White, W. N.; Wolfarth, E. F. (1970). "The o-Claisen rearrangement. VIII. Solvent effects". J. Org. Chem. 35 (7): 2196. doi:10.1021/jo00832a019. 
  12. ^ White, William; and Slater, Carl, William N.; Slater, Carl D. (1961). "The ortho-Claisen Rearrangement. V. The Products of Rearrangement of Allyl m-X-Phenyl Ethers". The Journal of Organic Chemistry 26 (10): 3631–3638. doi:10.1021/jo01068a004. 
  13. ^ Gozzo, Fábio; Fernandes, Sergio; Rodrigues, Denise; Eberlin, Marcos; and Marsaioli, Anita, Fábio Cesar; Fernandes, Sergio Antonio; Rodrigues, Denise Cristina; Eberlin, Marcos Nogueira; Marsaioli, Anita Jocelyne (2003). "Regioselectivity in Aromatic Claisen Rearrangements". The Journal of Organic Chemistry 68 (14): 5493–5499. doi:10.1021/jo026385g. PMID 12839439. 
  14. ^ a b c d László Kürti; Barbara Czakó (2005). Strategic Applications Of Named Reactions In Organic Synthesis: Background And Detailed Mechanics: 250 Named Reactions. Academic Press. ISBN 978-0-12-429785-2. Retrieved 27 March 2013.  edit
  15. ^ Adams, Rodger (1944). Organic Reactions, Volume II. Newyork: John Wiley & Sons, Inc. pp. 11–12. 
  16. ^ Claisen, L.; Eisleb, O. (1913). "Über die Umlagerung von Phenolallyläthern in die isomeren Allylphenole". Justus Liebigs Annalen der Chemie 401 (1): p. 90. doi:10.1002/jlac.19134010103. 
  17. ^ Malherbe, R.; Bellus, D. (1978). "A New Type of Claisen Rearrangement Involving 1,3-Dipolar Intermediates. Preliminary communication". Helv. Chim. Acta 61 (8): 3096–3099. doi:10.1002/hlca.19780610836. 
  18. ^ Malherbe, R.; Rist, G.; Bellus, D. (1983). "Reactions of haloketenes with allyl ethers and thioethers: A new type of Claisen rearrangement". J. Org. Chem. 48 (6): 860–869. doi:10.1021/jo00154a023. 
  19. ^ Gonda, J. (2004). "The Belluš–Claisen Rearrangement". Angew. Chem. Int. Ed. 43 (27): 3516–3524. doi:10.1002/anie.200301718. 
  20. ^ Wick, A. E.; Felix, D.; Steen, K.; Eschenmoser, A. (1964). "CLAISEN'sche Umlagerungen bei Allyl- und Benzylalkoholen mit Hilfe von Acetalen des N, N-Dimethylacetamids. Vorläufige Mitteilung". Helv. Chim. Acta 47 (8): 2425–2429. doi:10.1002/hlca.19640470835. 
  21. ^ Wick, A. E.; Felix, D.; Gschwend-Steen, K.; Eschenmoser, A. (1969). "CLAISEN'sche Umlagerungen bei Allyl- und Benzylalkoholen mit 1-Dimethylamino-1-methoxy-äthen". Helv. Chim. Acta 52 (4): 1030–1042. doi:10.1002/hlca.19690520418. 
  22. ^ Ireland, R. E.; Mueller, R. H. (1972). "Claisen rearrangement of allyl esters". Journal of the American Chemical Society 94 (16): 5897. doi:10.1021/ja00771a062.  edit
  23. ^ Ireland, R. E.; Willard, A. K. (1975). "The stereoselective generation of ester enolates". Tetrahedron Lett. 16 (46): 3975–3978. doi:10.1016/S0040-4039(00)91213-9. 
  24. ^ Ireland, R. E.; Mueller, R. H.; Willard, A. K. (1976). "The ester enolate Claisen rearrangement. Stereochemical control through stereoselective enolate formation". Journal of the American Chemical Society 98 (10): 2868. doi:10.1021/ja00426a033.  edit
  25. ^ Johnson, W. S. et al. (1970). "Simple stereoselective version of the Claisen rearrangement leading to trans-trisubstituted olefinic bonds. Synthesis of squalene". J. Am. Chem. Soc. 92 (3): 741. doi:10.1021/ja00706a074.  |first3= missing |last3= in Authors list (help); |first4= missing |last4= in Authors list (help); |first5= missing |last5= in Authors list (help); |first6= missing |last6= in Authors list (help); |first7= missing |last7= in Authors list (help)
  26. ^ IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997). XML on-line corrected version: http://goldbook.iupac.org (2006–) created by M. Nic, J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8. doi:10.1351/goldbook
  27. ^ Kurth, M. J.; Decker, O. H. W. (1985). "Enantioselective preparation of 3-substituted 4-pentenoic acids via the Claisen rearrangement". J. Org. Chem. 50 (26): 5769–5775. doi:10.1021/jo00350a067. 
  28. ^ Dauben, W. G.; Michno, D. M. (1977). "Direct oxidation of tertiary allylic alcohols. A simple and effective method for alkylative carbonyl transposition". J. Org. Chem. 42 (4): 682. doi:10.1021/jo00424a023. 
  29. ^ (R)-(+)-3,4-Dimethylcyclohex-2-en-1-one ((R)-(+)-3,4-Dimethyl-2-cyclohexen-1-one), Org. Synth. 82, 2005: 108 
  30. ^ Chen, B.; Mapp, A. (2005). "Thermal and catalyzed 3,3-phosphorimidate rearrangements". Journal of the American Chemical Society 127 (18): 6712–6718. doi:10.1021/ja050759g. PMID 15869293.  edit
  31. ^ Overman, L. E. (1974). "Thermal and mercuric ion catalyzed [3,3]-sigmatropic rearrangement of allylic trichloroacetimidates. 1,3 Transposition of alcohol and amine functions". Journal of the American Chemical Society 96 (2): 597–599. doi:10.1021/ja00809a054.  edit
  32. ^ Overman, L. E. (1976). "A general method for the synthesis of amines by the rearrangement of allylic trichloroacetimidates. 1,3 Transposition of alcohol and amine functions". Journal of the American Chemical Society 98 (10): 2901–2910. doi:10.1021/ja00426a038.  edit
  33. ^ Organic Syntheses, Coll. Vol. 6, p.507; Vol. 58, p.4 (Article)
  34. ^ Yu, C.-M.; Choi, H.-S.; Lee, J.; Jung, W.-H.; Kim, H.-J. (1996). "Self-regulated molecular rearrangement: Diastereoselective zwitterionic aza-Claisen protocol". J. Chem. Soc., Perkin Trans. 1 (2): 115–116. doi:10.1039/p19960000115. 
  35. ^ Nubbemeyer, U. (1995). "1,2-Asymmetric Induction in the Zwitterionic Claisen Rearrangement of Allylamines". J. Org. Chem. 60 (12): 3773–3780. doi:10.1021/jo00117a032. 
  36. ^ Ganem, B. (1996). "The Mechanism of the Claisen Rearrangement: Déjà Vu All over Again". Angew. Chem. Int. Ed. Engl. 35 (9): 936–945. doi:10.1002/anie.199609361. 

See also[edit]