Organophosphate (OP) pesticides are responsible for numerous human deaths every year. Nucleophilic substitution is an important method to mitigate the toxicity of obsolete stocks of OPs. Herein, the degradation of O,O-diethyl-2,4-dinitrophenyl phosphate (DEDNPP) and pesticide diethyl-4-nitrophenyl phosphate (Paraoxon) promoted by 1,2,4-triazole (TAZ) was investigated by means of kinetic studies, nuclear magnetic resonance (NMR) analyses, and theoretical calculations. Results showed fast degradation of OPs is promoted by the anionic form of the nucleophile (TAZ(−)) in pH > 8.5 (optimal at pH = 11). Rate enhancements of 106 and 105-fold in relation to neutral hydrolysis of DEDNPP and Paraoxon were observed, respectively, consistent with alpha-nucleophiles reactivity. TAZ(−) regioselectively promotes the degradation of DEDNPP via P–O bond break, forming a quickly hydrolyzable phosphorylated intermediate, regenerating the nucleophile. Calculations using M06-2X/6-311++G­(d,p) level of theory revealed that the equivalent nitrogen atoms of TAZ(−) are the main nucleophilic center of the molecule. This study expands the knowledge on the reactivity of iminic compounds as detoxificant agents of OPs, indicating the efficiency and selectivity of TAZ(−) in aqueous medium, encouraging the design of novel TAZ-based catalysts.

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The competitive formation of isomeric bridged lactams via acid-catalyzed intramolecular Schmidt reactions from 3-azidoethylcyclopentanones is explored using density functional theory (DFT) calculations, primarily performed at M06-2X/6-311++G(d,p) level of theory. Results...

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Herein we describe the synthesis, structural, spectroscopic and magnetic characterization of a new pentacoordinated bicopper(II) complex containing 2‐formylpyridine semicarbazone (HSCpy), referred as complex 1. Each copper core is bound to one N,N,O‐tridentate HSCpy ligand and connected to the second metal ion by two μ‐oxygen sulfato‐bridges. The compound shows an extensive association between the neutral complex molecule and water as crystallization solvate through classical N−H⋅⋅⋅O, O−H⋅⋅⋅O and, non‐classical C−H⋅⋅⋅O intermolecular hydrogen bonding generating a supramolecular 3‐D assembly in the solid state. Jahn‐Teller stabilization energies at 5144 cm−1 and spin orbit coupling constants λ=−442 cm−1 were estimated using the electronic spectra and Electron Paramagnetic Resonance data. The variable‐temperature (2‐300 K) magnetic measurements showed isotropic magnetic interaction between the two copper ions, according to the spin Hamiltonian yielding 2 J values at −0.34 cm−1 for complex 1, in accordance with a very small antiferromagnetic interaction between copper ions kept apart by 3.24 Å. The results are compared to the thiosemicarbazone analogue.