Home
Deutsch
Advanced Search
Browse by ...
Publication overview
Contact persons
Help
DOI
 |
|
Open Access Green as soon as Postprint is submitted to ZB.
Hydrolysis of mefenpyrdiethyl: An analytical and DFT investigation.
Anal. Bioanal. Chem. 398, 2325-2334 (2010)
The hydrolysis of the herbicide safener mefenpyrdiethyl (1-(2, 4-dichlorophenyl)-4, 5-dihydro-5-methyl-1H-pyrazole-3,5-dicarboxylic acid diethyl ester) was investigated in aqueous solutions in the pH range from 2 to 9 and the temperature range from 298 to 323 K. The kinetics of hydrolysis were pseudo first order and were found to be strongly pH and temperature dependent. While near-constant in acidic medium, the hydrolysis rates strongly increased in alkaline pH, and total hydrolysis was observed at pH 11. Two main hydrolysis products, mefenpyrethyl (monoester) and mefenpyr (dicarboxylic acid) were isolated by ultrahigh-pressure liquid chromatography (UHPLC) and characterized using high-resolution Fourier transform ion cyclotron resonance mass spectroscopy (ICR-FT/MS) as well as H-1, C-13 and 2D NMR analyses. Additionally, a density functional theory (DFT) investigation explained the stability of the pesticide at pH 7 and the high reactivity of the pesticide in alkaline medium. The key nucleophilic reaction partner is hydroxyl ions instead of neutral water molecules. Furthermore, the calculated activation barrier for hydrolysis in alkaline medium is in agreement with the extrapolated and experimentally determined activation barrier at pH 14.
Altmetric
Additional Metrics?
Edit extra informations
Login
Publication type
Article: Journal article
Document type
Scientific Article
Keywords
Mefenpyrdiethyl; Hydrolysis; Kinetics; Hydrolysis products; OPTIMIZING LARGE MOLECULES; GEOMETRY OPTIMIZATION; ITERATIVE SUBSPACE; ABIOTIC HYDROLYSIS; IMPROVED ALGORITHM; DIRECT INVERSION; AQUEOUS-SOLUTION; DEGRADATION; SOIL; PESTICIDES
ISSN (print) / ISBN
1618-2642
e-ISSN
1618-2650
Quellenangaben
Volume: 398,
Issue: 5,
Pages: 2325-2334
Publisher
Springer
Publishing Place
Heidelberg
Non-patent literature
Publications
Reviewing status
Peer reviewed
Institute(s)
Institute of Ecological Chemistry (IOEC)