A tandem mass spectrometric investigation of (C2H 5) 2X (+) ions (X = Cl, Br, I): The involvement of classical and nonclassical ethyl structures therein.
The formation of diethyl halonium ions (C2H5)2X(+) (X = Cl, Br, I) by a variety of ion-molecule reactions is described. The dissociation characteristics (metastable and collision-induced dissociation mass spectra) of these ions and their isomers were studied in detail. Some of the neutral fragmentation products were examined by their collision-induced dissociative ionization mass spectra.The participation of classical (1, CH3CH2X(+)CH2CH3) and nonclassical forms of the ions was considered. Dissociation reactions for which loss of positional identity of H-D atoms took place, for example C2H4 loss (a common fragmentation of metastable ions) and C2H5 (+) formation, were interpreted as involving nonclassical ions, 2. It was concluded that the ion-molecule reactions produced both ion structures, but in different halogen-dependent proportions. For (C2H5)2C1(+) ions, 2 is the major species, for (C2H5)2Br(+) both 1- and 2-type ions are generated, whereas for (C2H5)2I(+) the classical form 1 must be the predominant structure.
Chemistry Department, University of Ottawa, 10 Marie Curie, K1N 6N5, Ottawa, Ontario, Canada.
D V
DV
Zagorevskii
S P
SP
Palii
J L
JL
Holmes