38765-82-1Relevant articles and documents
Govil et al.
, p. 77,83, 85, 86, 89 (1978)
Mechanistic aspects of alkyne migration in alkylidene carbenoid rearrangements
Bichler, Paul,Chalifoux, Wesley A.,Eisler, Sara,Shi Shun, Annabelle L. K.,Chernick, Erin T.,Tykwinski, Rik R.
supporting information; experimental part, p. 519 - 522 (2009/07/17)
(Chemical Equation Presented) The mechanism of the Fritsch-Buttenberg- Wiechell rearrangement of 13C labeled precursors has been examined to determine the propensity of the alkynyl (R-C=C-) group to migrate in an alkylidene carbenoid species. R
Pseudo One-Step Cleavage of C-C Bonds in the Decomposition of Ionized Carboxyclic Acids. Radical Like Reactions in Mass Spectrometry
Weiske, Thomas,Schwarz, Helmut
, p. 323 - 347 (2007/10/02)
Metastable molecular ions of hexanoic acid (1) decompose unimolecularly to C2H5. and protonated methacrylic acid (5-H+)(92percent rel. abund.).Investigation of the mechanism reveals that 1) the branched cation radical 11 must be regarded as the essential intermediate in the course of the rearrangement/dissociation reaction and 2) the process commences with intramolecular hydrogen transfer from either C-3 or C-5 to the ionized carbonyl oxygen ("hidden" hydrogen migration).Hydrogen transfer from C-4, which would correspond to the well-known McLafferty rearrangement, is of no importance in the C2H5.-elimination from 1.The same conclusion applies for various alternative mechanisms, as for example a SRi type reaction, 1 -> 2-H+.The gas phase chemistry of the cation radical of 1, and in particular the hydrogen exchange processes between the methylene groups C-2/C-3 and C-5/C-6, is in surprisingly close correspondence to the chemistry of free alkyl radicals. - The syntheses of various 13C and 2H-labelled model compounds are described.
