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Electron Impact Induced Fragmentation of Dibenzo Crown Ethers

✍ Scribed by Kalevi Pihlaja; Silke Lehmann; Werner Schroth; Michael Gäbler; Erich Kleinpeter

Publisher
John Wiley and Sons
Year
1996
Tongue
English
Weight
310 KB
Volume
10
Category
Article
ISSN
0951-4198

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✦ Synopsis

Six structurally related crown ethers have been studied by electron impact @I) mass spectrometry. From accurate mass measurements, metastabel ion and mass-analyzed ion kinetic energy (MIKE) spectra, plausible fragmentation pathways were deduced. All compounds showed very abundant molecular ions and some amount of the doubly charged molecular ions. The primary fragmentations always involved the catechol moiety and consequent loss of oxirane although the fragment(ation)s also showed a clear dependence on the functionalities X in one of the crown ether segments, -OCH2XCHzO-(compoundfi: l/-CHz-, 2/-C=C-, 3 / t r a n s P H = CH-, 4 / c i s P H = CH-, 5/-HC+H-, and 6/-C€12CHr).

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