AWagner–Meerwein rearrangement is a class ofcarbocation1,2-rearrangementreactions in which ahydrogen,alkyl oraryl group migrates from one carbon to a neighboring carbon.[1][2] They can be described ascationic [1,2]-sigmatropic rearrangements, proceeding suprafacially and withstereochemical retention. As such, a Wagner–Meerwein shift is a thermally allowedpericyclic process with the Woodward-Hoffmann symbol [ω0s +σ2s]. They are usually facile, and in many cases, they can take place at temperatures as low as –120 °C. The reaction is named after the Russian chemistYegor Yegorovich Vagner; he had German origin and published in German journals as Georg Wagner; andHans Meerwein.
The story of the rearrangement reveals that many scientists were puzzled with this and related reactions and its close relationship to the discovery ofcarbocations as intermediates.[9]
Currently, there are works relating to the use of skeletal rearrangement in the synthesis of bridgedazaheterocycles. These data are summarized in[11]
Plausible mechanisms of the Wagner–Meerwein rearrangement ofdiepoxyisoindoles:
The relatedNametkin rearrangement, named afterSergey Namyotkin, involves the rearrangement of methyl groups in certain terpenes. In some cases the reaction type is also called aretropinacol rearrangement (seepinacol rearrangement).
^Popp, F. D.; McEwen, W. E. (1958). "Polyphosphoric Acids As a Reagent in Organic Chemistry".Chem. Rev.58 (2): 375.doi:10.1021/cr50020a004.
^Cargill, Robert L.; Jackson, Thomas E.; Peet, Norton P.; Pond, David M. (1974). "Acid-catalyzed rearrangements of β,γ-unsaturated ketones".Acc. Chem. Res.7 (4):106–113.doi:10.1021/ar50076a002.
^Hogeveen, H.; Van Krutchten, E. M. G. A. (1979). "Wagner-meerwein rearrangements in long-lived polymethyl substituted bicyclo[3.2.0]heptadienyl cations".Top. Curr. Chem. Topics in Current Chemistry.80:89–124.doi:10.1007/BFb0050203.ISBN3-540-09309-5.{{cite journal}}: CS1 maint: multiple names: authors list (link)
^Polito, Victoria; Hamann, Christian S.; Rhile, Ian J. (2010). "Carbocation Rearrangement in an Electrophilic Aromatic Substitution Discovery Laboratory".Journal of Chemical Education.87 (9): 969.Bibcode:2010JChEd..87..969P.doi:10.1021/ed9000238.
^Zubkov, F. I.; Zaytsev, V. P.; Nikitina, E. V.; Khrustalev, V. N.; Gozun, S. V.; Boltukhina, E. V.; Varlamov, A. V. (2011). "Skeletal Wagner–Meerwein rearrangement of perhydro-3a,6;4,5-diepoxyisoindoles".Tetrahedron.67 (47): 9148.doi:10.1016/j.tet.2011.09.099.
