JMSSJ On-line

JMSSJ On-line, Vol. 50 (2002) No. 4, pp. 193-198

Unimolecular Metastable Decomposition of Bis(2,2,2-trifluoroethyl) Ether, CF₃CH₂OCH₂CF₃, and Ethyl 2,2,2-Trifluoroethyl Ether, CH₃CH₂OCH₂CF₃, upon Electron Ionization		>> Full Text PDF >> References
*Susumu TAJIMA,^a) Osamu SEKIGUCHI,^a) Satoshi NAKAJIMA,^a) and Nico M.M. NIBBERING^b)** ^*a) Chemistry and Materials Science, Gunma National College of Technology ( Maebashi, Gunma 371-8530, Japan) ^b) Laser Centre and Chemistry Department, Free University ( De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands)

The unimolecular metastable decompositions of bis(2,2,2-trifluoroethyl) ether, CF₃CH₂OCH₂CF₃ (1), and ethyl 2,2,2-trifluoroethyl ether, CH₃CH₂OCH₂CF₃ (2), induced by electron ionization, have been investigated by mass-analyzed ion kinetic energy (MIKE) spectrometry and energy-dependent collision-induced dissociation (CID) spectra in conjunction with thermochemical data. In the metastable time window, the molecular ions of 1 decompose into the ions at m/z 113 by the loss of CF and m/z 83 by the consecutive losses of CF and CH₂O, while those of 2^{+ •} decompose into the ions at m/z 113 and m/z 59 by the elimination of CH and CF , respectively. The decomposition of the latter fragment ion is similar to that of the m/z 59 ion from the corresponding fluorine-free analogue, diethyl ether, CH₃CH₂OCH₂CH₃ (3), that is, fragment ions m/z 41 and m/z 31 are observed, which correspond to the competitive losses of H₂O and C₂H₄, respectively. The metastable ions m/z 113 from 1^{+ •} and 2^{+ •} decompose in a variety of ways: in addition to the fragment ion m/z 65, which is generated by the elimination of CHFO, four other fragment ions with m/z 83, 63, 61, and 31 are observed , which correspond to the competitive losses of CH₂O, (CH₂O+HF), CH₂F₂, and C₂HF₃ (or C₂H₄F₂O), respectively.

Key words: Keywords :Organo uorocompounds,MIKE spectra,Thermo-chemistry,CHFO loss,Energy-dependent CID spectra

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