The electron ionization (EI)-induced fragmentations of a series of 1,1-(2,2'-dimethoxyphenyl)-substituted 2-methylpropanes (1-20) in both 70 eV and mass-analyzed ion kinetic energy (MIKE) spectra have been investigated. The EI-MS spectra of these compounds are characterized by the presence of abundant benzyl ions. These ions result from competitive hydrogen migration from the 2- and 2'-methoxy groups on the carbenium center of the diphenylmethyl cations formed by benzylic cleavage of the molecular ions. The relative abundances of the benzyl ions arising from such competitive processes are discussed and rationalized. The steric effect of the 3- or 3'-substituents is the main discriminating factor between the two competitive processes. The structural information, arising either from the 70 eV or the MIKE spectra, is discussed.

BONGIORNO D, CERAULO L, FILIZZOLA F, FONTANA G, & NATOLI M C (2006). Benzyl ions from 1,1-(2,2'-dimethoxyphenyl)-substituted 2-methylpropanes under electron ionization. RAPID COMMUNICATIONS IN MASS SPECTROMETRY, 20(20), 3081-3088 [10.1002/rcm.2687].

Benzyl ions from 1,1-(2,2'-dimethoxyphenyl)-substituted 2-methylpropanes under electron ionization

BONGIORNO, David;CERAULO, Leopoldo;FILIZZOLA, Felice;FONTANA, Gianfranco;NATOLI, Maria Concetta
2006

Abstract

The electron ionization (EI)-induced fragmentations of a series of 1,1-(2,2'-dimethoxyphenyl)-substituted 2-methylpropanes (1-20) in both 70 eV and mass-analyzed ion kinetic energy (MIKE) spectra have been investigated. The EI-MS spectra of these compounds are characterized by the presence of abundant benzyl ions. These ions result from competitive hydrogen migration from the 2- and 2'-methoxy groups on the carbenium center of the diphenylmethyl cations formed by benzylic cleavage of the molecular ions. The relative abundances of the benzyl ions arising from such competitive processes are discussed and rationalized. The steric effect of the 3- or 3'-substituents is the main discriminating factor between the two competitive processes. The structural information, arising either from the 70 eV or the MIKE spectra, is discussed.
BONGIORNO D, CERAULO L, FILIZZOLA F, FONTANA G, & NATOLI M C (2006). Benzyl ions from 1,1-(2,2'-dimethoxyphenyl)-substituted 2-methylpropanes under electron ionization. RAPID COMMUNICATIONS IN MASS SPECTROMETRY, 20(20), 3081-3088 [10.1002/rcm.2687].
File in questo prodotto:
File Dimensione Formato  
Bongiorno_et_al-2006-Rapid_Communications_in_Mass_Spectrometry.pdf

non disponibili

Dimensione 183.71 kB
Formato Adobe PDF
183.71 kB Adobe PDF   Visualizza/Apri   Richiedi una copia

I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.

Utilizza questo identificativo per citare o creare un link a questo documento: http://hdl.handle.net/10447/25869
Citazioni
  • ???jsp.display-item.citation.pmc??? 0
  • Scopus 0
  • ???jsp.display-item.citation.isi??? 0
social impact