Inverse stereochemical effects in the mass spectra of carboalkoxycyclopropylsilanes

K. Vékey, József Tamás, Gábor Czira, Igor E. Dolgy

Research output: Contribution to journalArticle

2 Citations (Scopus)

Abstract

The electron impact induced decomposition of the cis and trans isomeric pairs of five 1‐trialkylsilyl‐2‐alkoxy‐carbonylcyclopropanes were investigated. Compared with carbon analogues, the silicon atom inhibited ring opening and dramatically altered the fragmentation. The main primary decomposition routes were alkyl loss from silicon, and trialkylsilyl ion formation as well as trialkylalkoxysilane elimination. An unexpected inverse stereochemical effect was found for this latter reaction which was far less significant for the cis isomers, where the interacting SiQ3 and OR groups are close to each other, than for the trans isomers. This is explained by assuming a hidden silicon‐oxygen bond formation, which is possible only in the cis isomers for geometric reasons. This interaction favours alkyl elimination over other fragmentations, and has a marked effect on the further decomposition of the [M—alkyl]+ ions, where observed differences in abundance as great as three orders of magnitude are accounted for.

Original languageEnglish
Pages (from-to)620-626
Number of pages7
JournalOrganic Mass Spectrometry
Volume17
Issue number12
DOIs
Publication statusPublished - 1982

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Silicon
Isomers
mass spectra
isomers
Ions
Decomposition
decomposition
elimination
fragmentation
Carbon
silicon
Electrons
electron impact
ions
routes
analogs
Atoms
carbon
rings
atoms

ASJC Scopus subject areas

  • Biochemistry
  • Molecular Medicine
  • Instrumentation

Cite this

Inverse stereochemical effects in the mass spectra of carboalkoxycyclopropylsilanes. / Vékey, K.; Tamás, József; Czira, Gábor; Dolgy, Igor E.

In: Organic Mass Spectrometry, Vol. 17, No. 12, 1982, p. 620-626.

Research output: Contribution to journalArticle

Vékey, K. ; Tamás, József ; Czira, Gábor ; Dolgy, Igor E. / Inverse stereochemical effects in the mass spectra of carboalkoxycyclopropylsilanes. In: Organic Mass Spectrometry. 1982 ; Vol. 17, No. 12. pp. 620-626.
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