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Updated: May 5, 2026

Determination of the Gas-phase Acidities of Oligopeptides
Published on: June 24, 2013
Gas-phase ion-molecule reactions of the CH3O (+) cation
H W Zappey1, S Ingemann, N M Nibbering
1Institute of Mass Spectrometry, University of Amsterdam, Nieuwe Achtergracht 129, NL-1018 WS, Amsterdam, The Netherlands.
Abstract:
The methoxy cation, CH30(+), formed by collision-induced charge reversal of methoxr anions with a kinetic energy of 8 keY, has been differentiated from the isomenric CH2OH(+) ion by performing low kinetic energy ion-molecule reactions In the radiofrequency-only quadrupole of a reverse-geometry double-focusing quadrupole hybrid mass spectrometer. The methoxy cation reacts with CH3SH, CH3-CH=CH2, (CH3)2O, and CH3CH2Cl by electron transfer, whereas the CH2OH(+) ion reacts by proton transfer with these substrates.
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