Stabilization of the pesticide Fenitrothion towardOandNnucleophiles in the presence of cyclodextrins

Abstract

The reaction of Fenitrothion with O and N nucleophiles (H 2 O 2 , NH 2 OH, n-butylamine and piperidine) was studied at 25°C in water containing 2% 1,4-dioxane in the presence of native cyclodextrins (α-, β-, and γ-CD). For all the nucleophiles, the presence of CD produces reaction inhibition with saturation kinetics. The greatest effect in all cases is observed with β-CD, and the greatest inhibition was observed for the reaction of Fenitrothion with H 2 O 2 (81%), which is the most efficient nucleophile in promoting Fenitrothion degradation in homogeneous media. In the absence of CD, competition between the S N 2(P) and the S N 2(C) pathways was observed with piperidine as was reported before for the reaction with NH 2 OH and n-butylamine. The presence of β-CD does not modify product distribution in the case of the reaction with NH 2 OH and n-butylamine, whereas there is an increase in S N 2(C) pathway when the nucleophile is piperidine.

Trifluralin and two of its photodegradation products: Crystal structures and phase solubility/UV studies with cyclodextrins

“…We have previously studied the interaction of native and methylated CDs with other herbicides and some organophosphorus insecticides both in solution and in the solid state, and the effect of the encapsulation on the reactivity of some of them . The present paper deals with our results on the interaction of 1 , 2 , and 3 with β‐CD in solution and with native and modified CDs in the solid state.…”

Rapid cleavage of phosphate triesters by the oxime 2‐(hydroxyimino)‐N‐phenyl‐acetamide

“…A convenient approach to OP decomposition is the reaction with strong nucleophiles, such as hydroxylamine, and hydroxamic acids, which furnish insights into the development of systems suited for the detoxification of OP warfare agents. Additionally, microheterogeneous systems have been proposed for the cleavage of phosphate esters, which explore important non‐covalent effects for enhancing experimental rates.…”