79144-64-2Relevant articles and documents
On the McLafferty Rearrangement of Ionized Phenyl Pyridyl Alkanones
Richter, Bernd,Schwarz, Helmut
, p. 865 - 877 (2007/10/02)
A detailed investigation concerning the genesis of McLafferty rearrangement products from molecular ions of phenyl pyridyl alkanones reveals the following features: 1) The various products are not formed by competitive dissociations of the molecular ion.Most of the relevant fragment ions are generated from the primary McLafferty product of a hydrogen transfer to the ionized carbonyl group (M+*-->m/z 163, ion k).The ion k plays a decisive role for the generation of the abundant product ions at m/z 93 (ion g) and m/z 106 (ion s) both of which are formed by further dissociation of k.Details of the mechanisms for the decomposition of k are obtained by investigating -labelled isotopomers, the analysis of low and high resolution data, the application of MIKE and CA spectra.The problem of keto/enol tautomerism between some ions, relevant in this context, is discussed and it is shown that these isomerization processes are not involved.A detailed description is given for the syntheses of various -labelled phenyl pyridyl alkanones. - Keywords: Mass Spectrometry, Hydrogen Rearrangement, Keto Enol Tautomerism, Metastable Ions, Collisional Activation
