Gas-phase bimolecular chemistry of isomeric cyclic ethylenehalonium and α-haloethyl cations

✍ Scribed by Albert J. R. Heck; Leo J. de Koning; Nico M. M. Nibbering

• Publisher: John Wiley and Sons
• Year: 1993
• Tongue: English
• Weight: 863 KB
• Volume: 28
• Category: Article
• ISSN: 1076-5174
• DOI: 10.1002/oms.1210280316

✦ Synopsis

The gas-phase bimolecular chemistry of C2H4X+ (X = F, C1, Br) cations was studied using Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR-MS). The results support earlier suggestions that at least two isomers of the halonium ions C2H4X+ (X = CI, Br) exist, but no experimental evidence was found for the possibility of more than one stable isomer for C2H4F+. It is shown that the cyclic ethylenehalonium and a-haloethyl cations react differently with various substrates. The probe reactions used to characterize the two isomers were hydrogen-deuterium exchange with deuterium oxide and reactions with benzene, alkenes and vinyl ethers. It was found that the a-haloethyl cations react as proton donors and/or electrophiles, whereas the cyclic ethylenechloronium and ethylenebromonium ions react as electrophile and/or as haloganyl cation donors in reactions with alkenes and vinyl ethers.