In:
Zeitschrift für Naturforschung B, Walter de Gruyter GmbH, Vol. 33, No. 10 ( 1978-10-1), p. 1150-1164
Abstract:
The details of the elimination of CH 3 · and C 2 H 5 · from the molecular ions of n-butyl and n-pentyl benzenes as well as the formation of C 7 H 7 + and C 7 H 7 + -have been established using a combination of different mass spectrometric techniques. Among these techniques are field ionization kinetics (FIK), collisional activation (CA), unimolecular decomposi-tion of metastable ions (MI), kinetic energy release determinations (Tkin) 〉 appearance potential measurements (AP) as well as high resolution mass spectrometry. The appli-cation of these methods and the investigation of nine 13 carbon and eleven deuterium labelled n-butyl and n-pentyl benzenes clearly demonstrate that 1) the loss of methyl and ethyl from terminal positions of the alkyl chains are accompanied by an interaction with the phenyl ring and 2) the regioselectivity of these processes is time dependent. Contrary to previous conclusions it is shown that hydrogen transfer in the formation of C 7 H 8 + -occurs via five-, six-and seven-membered transition states. The time dependence of the hydrogen exchange reaction preceding the alkene eliminations is discussed in detail.
Type of Medium:
Online Resource
ISSN:
1865-7117
,
0932-0776
DOI:
10.1515/znb-1978-1022
Language:
English
Publisher:
Walter de Gruyter GmbH
Publication Date:
1978
detail.hit.zdb_id:
2078109-X
detail.hit.zdb_id:
124635-5