Chemical Sciences: A Manual for CSIR-UGC National Eligibility Test for Lectureship and JRF/Named Reactions/Wagner-Meerwein Rearrangement

A Wagner-Meerwein rearrangement is a class of carbocation 1,2-rearrangement reactions in which a hydrogen, alkyl or aryl group migrates from one carbon to a neighboring carbon.Wagner, G. J. Russ. Phys. Chem. Soc. 1899, 31, 690. Hans Meerwein Über den Reaktionsmechanismus der Umwandlung von Borneol in Camphen; [Dritte Mitteilung über Pinakolinumlagerungen.] Justus Liebig's Annalen der Chemie 1914 405 129–175 10.1002/jlac.19144050202 Several reviews have been published.Popp, F. D.; McEwen, W. E. Chem. Rev. 1958, 58, 375. (Review)Cargill, R. L. et al. Accts. Chem. Res. 1974, 7, 106-113. (Review)Olah, G. A. Accts. Chem. Res. 1976, 9, 41. (Review)Hogeveen, H.; Van Krutchten, E. M. G. A. Top. Curr. Chem. 1979, 80, 89-124. (Review)Hanson, J. R. Comp. Org. Syn. 1991, 3, 705-719. (Review) The rearrangement was first discovered in bicyclic terpenes for example the conversion of isoborneol to camphene: Isoborneol Camphene Conversion The story of the rearrangement reveals that many scientists were puzzled with this and related reactions and its close relationship to the discovery of carbocations as intermediates.Birladeanu, L. J. Chem. Ed. 2000, 77, 858-863. The related Nametkin rearrangement named after Sergey Namyotkin involves the rearrangement of methyl groups in certain terpenes. In some cases the reaction type is also called a retropinacol rearrangement (see Pinacol rearrangement). References