AI Article Synopsis
- The study investigated how the insecticide ethophenprox fragments in the presence of protons using advanced mass spectrometry techniques.
- Despite expectations, protonated ethophenprox ions were not detected in certain solvents, leading to the identification of an unexpected ion with m/z 359.
- The formation of this m/z 359 ion was largely attributed to a loss of water through a specific structural rearrangement process, primarily following a six-centered pathway.
Article Abstract
We elucidated the mechanism of fragmentation of ethophenprox (Mw = 376), a non-ester pyrethroid insecticide, in the presence of a proton, by using tandem mass spectrometry in combination with an atmospheric pressure chemical ionization technique in positive-ion mode. When methanol or acetonitrile was used as a solvent, no protonated ethophenprox ion was observed in the mass spectra even at low cone voltage (10 V), at which solvent cluster ions can exist. Instead of the protonated ion, an unexpected m/z 359 ion was strongly observed under all conditions examined. The product ion spectrum of the m/z 359 ion obtained under low collision energy (20 eV) showed that this ion can be formed through structural rearrangement involving water loss mainly via the six-centered pathway in this system, although two pathways (five-centered and six-centered) to form the m/z 359 ion are suggested in the literature.
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| http://dx.doi.org/10.1255/ejms.976 | DOI Listing |
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