Premium
Electron ionization‐induced fragmentation of N ‐ and O ‐alkoxymethylated carbostyril and phenanthridinone
Author(s) -
Szmigielski Rafał,
Danikiewicz Witold
Publication year - 2004
Publication title -
journal of mass spectrometry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.475
H-Index - 121
eISSN - 1096-9888
pISSN - 1076-5174
DOI - 10.1002/jms.652
Subject(s) - chemistry , fragmentation (computing) , electron ionization , medicinal chemistry , ionization , ion , aldehyde , alkyl , molecule , stereochemistry , organic chemistry , computer science , catalysis , operating system
Unimolecular fragmentation patterns of N ‐alkoxymethylated carbostyril and phenanthridinone and their O ‐alkoxymethyl isomers were studied. The main fragmentation reaction observed for the studied compounds is the elimination of an aldehyde molecule. The main products of this reaction are the appropriate N ‐methyl derivatives, but ions with other structures are also formed. This reaction is supposed to proceed via 1,3‐H shift in the alkoxymethyl group in the case of the N ‐alkoxymethyl derivatives and by a multi‐step mechanism for O ‐alkoxymethylated compounds. Another important fragmentation common for all studied compounds is the loss of an alkyl radical from N ‐ and O ‐alkoxymethyl groups, yielding the appropriate stable isomeric cations, which, according to the results of the further fragmentation, undergo fast equilibration reaction via an ion–neutral complex. This process is accompanied by the unusually high kinetic energy release value. Copyright © 2004 John Wiley & Sons, Ltd.