5789-30-0Relevant articles and documents
Verification of stereospecific dyotropic racemisation of enantiopure d and l-1,2-dibromo-1,2-diphenylethane in non-polar media
Christopher Braddock,Roy, Debjani,Lenoir, Dieter,Moore, Edward,Rzepa, Henry S.,Wu, Judy I-Chia,Von Rague Schleyer, Paul
supporting information, p. 8943 - 8945 (2012/11/13)
The first example of a dyotropic rearrangement of an enantiomerically pure, conformationally unconstrained, vicinal dibromide confirms theoretical predictions: d and l-1,2-dibromo-1,2-diphenylethane racemise stereospecifically in refluxing benzene without crossover to the meso-isomer. An orbital analysis of this six-electron pericyclic process is presented.
Bromination of Alkenes in Acetonitrile. A Rate and Product Study
Bellucci, Giuseppe,Bianchini, Roberto,Chiappe, Cinzia
, p. 3067 - 3073 (2007/10/02)
The reaction of simple alkenes and aryl alkenes with molecular bromine in damp MeCN occurred with solvent incorporation to give 2-bromo-1-(N-acetylamino)alkanes, 2-methyloxazolines, 2-acetoxyalkylamine hydrobromides, and 2-(N-acetylamino) alcohols.These products arose by the transformation of initially formed 2-bromo-1-(N-acetylamino)alkanes obtained by MeCN attack on bromonium or bromocarbonium ions to give nitrilium tribromide salts.These reacted with water to give 2-bromo-1-(N-acetylamino)alkanes.The kinetic profile of the reaction showed a very fast initial reaction of the alkene and Br2 to yield the nitrilium tribromide, followed by a much slower reaction of Br3(1-) with the alkene.The incorporation of MeCN was Markovnikov and stereospecifically anti.The degree to which incorporation of solvent occurred depended upon the alkene structure and the initial reagent concentrations.A rationalization for the observed chemoselectivity and its dependence on the reaction conditions is offered.