Pesticide contamination is a global issue, affecting nearly 44% of the global farming population, and disproportionately affecting farmers and agricultural workers in developing countries. Despite this, global pesticide usage is on the rise, with the growing demand of global food production with increasing population. Different types of porous materials, such as carbon and zeolites, have been explored for the remediation of pesticides from the environment. However, there are some limitations with these materials, especially due to lack of functional groups and relatively modest surface areas. In this regard, metal–organic frameworks (MOFs) provide us with a better alternative to conventionally used porous materials due to their versatile and highly porous structure. Recently, a number of MOFs have been studied for the extraction of pesticides from the environment as well as for targeted and controlled release of agrochemicals. Different types of pesticides and conditions have been investigated, and MOFs have proved their potential in agricultural applications. In this review, the latest studies on delivery and extraction of pesticides using MOFs are systematically reviewed, along with some recent studies on greener ways of pest control through the slow release of chemical compounds from MOF composites. Finally, we present our insights into the key issues concerning the development and translational applications of using MOFs for targeted delivery and pesticide control.

A kinetic study of the chemiluminescent (CL) reaction mechanism of lophine-derived hydroperoxides and silylperoxides induced by a base and fluoride, respectively, provided evidence for the formation of a 1,2-dioxetane as a high-energy intermediate (HEI) of this CL transformation. This was postulated using a linear Hammett relationship, consistent with the formation of negative charge on the transition state of HEI generation (ρ > 1). The decomposition of this HEI leads to chemiexcitation with overall low singlet excited state formation quantum yield (ΦS from 1.1 to 14.5 × 10–5 E mol–1); nonetheless, ΦS = 1.20 × 10–3 E mol–1 was observed with both peroxides substituted with bromine. The use of electron-donating substituents increases chemiexcitation efficiency, while it also reduces the rate for both formation and decomposition of the HEI. Different possible pathways for HEI decomposition and chemiexcitation are discussed in light of literature data from the perspective of the substituent effect. This system could be explored in the future for analytical and labeling purposes or for biological oxidation through chemiexcitation.

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The kinetics of the decomposition reaction of 4-(4,5-diphenyl-1H-imidazol-2-yl)phenyl acetate (1) in basic alcoholic media was investigated, using a simple fluorescence (FL) spectrophotometric procedure. The process was conveniently studied using FL, since the triphenylimidazole-derived ester 1 and its reaction products (the corresponding phenol 2 and phenolate 2 − ) are all highly fluorescent (Φ FL > 37%). By carefully selecting excitation and emission wavelengths, observed rate constants k 1 in the order of 10 −3 to 10 −2 s −1 were obtained from either reactant consumption (λ ex = 300 nm, λ em = 400 nm) or product formation (λ ex = 350 nm, λ em = 475 nm); these were shown to be kinetically equivalent. Intensity-decay time profiles also gave a residual FL intensity parameter, shown to be associated to the distribution of produced species 2 and 2 − , according to the basicity of the medium. Studying the reaction in both methanol (MeOH) and isopropanol (iPrOH), upon addition of HO − , provided evidence that the solvent's conjugate base is the active nucleophilic species.When different bases were used (tBuO − , HO − , DBU and TEA), bimolecular rate constants k bim ranging from 4.5 to 6.5 L mol −1 s −1 were obtained, which proved to be non-dependent on the base pK aH , suggesting specific base catalysis for the decomposition of 1 in alcoholic media. KEYWORDS imidazole, kineticslight emissionlophine, rate constant 1 | INTRODUCTIONThe triphenylimidazole structural framework has been intensely studied throughout the years, by many different research groups, due to its fluorescence (FL) [1][2][3][4][5][6][7][8][9] and chemiluminescence (CL) [10][11][12][13][14][15][16][17][18][19][20][21][22] properties. The typical direct CL of 2,4,5-triphenylimidazole (also known as lophine) with oxygen in an alkaline media, first described by Radziszewski in 1877, [23] was studied mainly to elucidate its reaction mechanism. [11][12][13][18][19][20][21][22]24] However, lophine and its derivatives were also applied in other CL systems, being used as activators of the peroxyoxalate reaction [10] or enhancers of the luminol transformation. [25][26][27] In part, the vast array of application of these molecules, from FL to CL measurements, depends on the high FL quantum yields (Φ FL > 0.1) presented by them. [1][2][3][4][5][6][7][8][9][10]17,[24][25][26][27] In 1993, Kuroda et al. reported that triphenylimidazole-para-acetate (1, IUPAC name 4-(4,5-diphenyl-1H-imidazol-2-yl)phenyl acetate), as well as another three ester analogs based on pertinent fatty acids, could be applied on the evaluation of lipase activity through FL measurements. [8] Although ester 1 itself was not the most suitable for interaction with the lipase, it was primarily used to define the methodology for activity determination. Briefly, the method consisted on hydrolyzing the ester with the enzyme, followed by separation and FL