Redoxaktive N‐(Fluormethoxy)benzotriazole wurden aus Fluoressigsäure und Hydroxybenzotriazolen durch elektrocarboxylative Kopplung zugänglich gemacht. Nach Alkylierung werden diese zu wirksamen ...Monofluormethoxylierungsreagenzien, welche die photokatalytische C‐H‐Funktionalisierung von Aromaten ermöglichen. Dadurch kann durch Bestrahlung von 1‐(OCH2F)‐3‐Me‐6‐(CF3)benzotriazoliumtriflat mit blauem LED‐Licht in Gegenwart von Ru(bpy)3(PF6)2 die Synthese von vielfältig funktionalisierten Arylmonofluormethylethern begünstigt werden. Diese Methode ermöglicht die späte Funktionalisierung biologisch relevanter Strukturen, ohne auf ökologisch problematische Halofluorkohlenwasserstoffe angewiesen zu sein.
A cost-effective and expeditious one-pot synthesis of 1-(2-bromo-1-arylethyl)-1H-benzotriazoles has been devised by reacting styrene and their derivatives with 1H-benzotriazole in presence of ...N-bromosuccinimide in anhydrous CH2Cl2 at room temperature. Further, the resulted compounds undergo E2-ellimination to afford the respective 1-(1-aryl-vinyl)-1H-benzotriazoles. At the end, 1-(1-phenylvinyl)-1H-benzotriazoles underwent benzotriazole ring cleavage (BtRC) under free radical condition to produce phenanthridine as the final product.
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•A novel and expeditious one-pot synthesis of 1-(2-bromo-1-arylethyl)-1H-benzotriazoles has been devised by reacting styrene with 1H-benzotriazole in presence of NBS in anhydrous CH2Cl2 at room temperature.•The resulted compounds undergo E2-ellimination to afford respective 1-(1-phenylvinyl)-1H-benzotriazoles.•1-(1-Phenylvinyl)-1H-benzotriazole underwent benzotriazole ring cleavage (BtRC) under free radical condition to produce phenanthridine.
An organoselenium-catalyzed N1- and N2-selective aza-Wacker reaction of alkenes with benzotriazoles is reported, which provides easy access to N1- and N2-olefinated benzotriazole derivatives. The ...wide substrate scope, good functional group tolerance, and facile scale-up of this method are expected to promote its potential application in synthetic chemistry. A preliminary mechanism is proposed to explain the N1- and N2-selectivities.
Benzotriazole ultraviolet absorbents (BUAs) of emerging concern were recently monitored in seawater and sediments from the Bohai Sea (BS) and North Yellow Sea (NYS), which are impacted by human ...activities, to elucidate their regional occurrence patterns, phase distributions, and contamination profiles. Although environmental variables such as sedimentary organic carbon, particle size, and salinity, as well as hydrological conditions, affected the environmental occurrence of BUAs in the BS and NYS, the source dependence of BUA distributions associated with urban impacts and riverine inputs was highlighted. Substantial spatial variability in the composition patterns and contamination profiles of BUAs identified through correlation and principal component analyses were likely caused by region-specific sources and characteristics. The distribution of target BUAs between the sediment and seawater phases showed no dependence on the octanol-water partition coefficient (KOW) but exhibited marked spatial variations. The diversity of BUA sorption behaviors was further explained by the total organic carbon (TOC)-normalized distribution coefficient (KTOC). Classic logKTOC-logKOW linear relationships accurately predicted the phase distributions of UV-326, UV-328, and UV-234, but deviations were found for lighter and heavier BUAs, possibly due to the influences of physical disturbance and microparticle binding.
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•Extensive surveys of BUAs in the Bohai and North Yellow Seas were conducted.•Spatially varying BUA profiles were controlled by region-specific sources.•Drometrizole trisiloxane as a benzotriazole UV filter pervade in the Bohai Sea.•Sediment-water distribution of BUAs was controlled by factors including TOC.
In recent years, power conversion efficiency (PCE) of organic solar cells (OSCs) has made significant improvement. A large number of studies were reported to achieve high PCEs through exploring new ...active layer materials, especially the high efficiency fused ring acceptors (FRAs). Compared with FRAs, another type of so-called unfused-ring acceptors (UFAs), possessing some advantages such as simple synthesis and low cost, have attracted a lot of attention. Herein, a new UFA
BTzO-4F
, incorporating with a benzotriazole moiety and S⋯O intramolecular noncovalent interactions, has been successfully synthesized. The photovoltaic device based on PBDB-T:
BTzO-4F
achieved a record PCE of 13.8% for UFAs, which indicates that introducing the benzotriazole moiety is an effective strategy for high quality acceptors. Thus, these findings of this work demonstrate the great potential of UFAs for high performance OSCs.
Benzotriazole UV-stabilizers (BUVs) are applied in materials for protection against UV-irradiation. They are widely used, bioaccumulate and share structural similarities to benzotriazole. ...Benzotriazole (1HBT) finds application as corrosion inhibitor in dishwashing detergents, antifreeze (vehicles) and aircraft de-icing agent. BUVs and 1HBT are persistent and ubiquitous in the aquatic environment, but there is little understanding of the ecotoxicological implications. Here, we comparatively analyze the hormonal activity in vitro and effects in zebrafish eleuthero-embryos in vivo. 2-(2-Hydroxy-5-methylphenyl)benzotriazole (UV-P), 2-(3-t-butyl-2-hydroxy-5-methylphenyl)-5-chlorobenzotriazole (UV-326), UV-327, UV-328, UV-329 and UV-320 showed no estrogenicity (YES assay) and androgenicity (YAS assay). However, UV-P and 1HBT showed significant antiandrogenic activity.
We assessed the transcription profiles of up to 26 genes associated with different toxicological pathways in zebrafish eleuthero-embryos to elucidate potential modes of action of UV-P, UV-326 and 1HBT. Embryos were experimentally exposed for 144hpf to three measured concentrations of 15.8, 70.8, and 690μg/L UV-P, 7.5, 31.7, and 84.3μg/L UV-326 and 7.9, 97.3 and 1197.3μg/L 1HBT. Among the 26 transcripts, the induction of the aryl hydrocarbon receptor (AHR) pathway by UV-P and UV-326 was the most significant finding. UV-P led to dose-related induction of AHR1, ARNT2 and cyp1a1, as well as of phase II enzymes glutathione-S-transferase (gstp1) and ugt1a. UV-326 led to a significant induction of cyp1a1 and AHR2, but down-regulation of gstp1 at 84μg/L. Only little transcriptional alterations occurred in genes related to apoptosis, oxidative stress, hormone receptors, and steroidogenesis including aromatase. 1HBT led to only a few expressional changes at 1197μg/L. Our data lead to the conclusion that UV-P and UV-326 activate the AHR-pathway, whereas 1HBT shows only little transcriptional alterations. It should be noted, however, that effects have been observed at concentration much higher than those occurring in the environment. Forthcoming studies should show whether the observed antiandrogenic activities and transcriptional changes translate into physiological effects .
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•Effects of benzotriazole UV-stabilizers and benzotriazoles are little known.•UV-P and 1HBT show antiandrogenic activity in the YAS.•A targeted transcription analysis with 26 genes is performed in zebrafish embryos.•UV-P and UV-326 are of the AHR pathway in zebrafish embryos.
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•GO/COF has excellent dispersion in epoxy resin.•GO/COF was used as nanocontainer for BTA.•The mechanism of adsorption and release of BTA by GO/COF was revealed.•GO/COF@BTA epoxy ...resin coating exhibits excellent self-healing ability.
Graphene oxide (GO) can enhance the corrosion resistance of epoxy coating, but there are problems such as poor filler dispersion and mechanical damage that will reduce the coating corrosion resistance. To resolve these problems, here, we used a facile and green liquid-phase synthetic strategy to grow covalent organic framework (COF) on GO sheets with 1,3,5-Triformylphloroglucinol and p-phenylenediamine as monomers for the COF synthesis. The COF could not only improve the compatibility of GO with epoxy coating, but also act as a nanocontainer for loading corrosion inhibitors. Electrochemical impedance spectroscopy showed that the low-frequency impedance of GO/COF-2% coating immersed in 3.5 wt% NaCl solution for 60 days was 8.58 × 108 Ω cm2. This was one order of magnitude higher than that of GO-2%, showing excellent corrosion resistance. Then, corrosion inhibitor of benzotriazole (BTA) was loaded into GO/COF, where the adsorption and release of BTA was controlled by environmental pH values. Results proved that the GO/COF@BTA-2% reinforced epoxy coating had superior corrosion resistance as well as self-healing ability because of the good compatibility, greater crosslinking density and controllable release of BTA.
Benzotriazole ultraviolet stabilizers (BUVSs) are high-production-volume chemicals with ubiquitous occurrence in the aquatic environment. However, little is known about their bioconcentration and ...biotransformation, and physiologically based toxicokinetic (PBTK) models for BUVSs are lacking. This study selected six BUVSs for which experiments were performed with zebrafish (Danio rerio) exposed to two different levels (0.5 and 10 μg·L–1). Higher kinetic bioconcentration factors (BCFs) were observed at the lower exposure level with environmental relevance, with BCF of 3.33 × 103 L·kg–1 for 2-(2-hydroxy-3,5-di-tert-butylphenyl)-5-chlorobenzotriazole (UV-327). This phenomenon was interpreted by a nonlinear adsorption mechanism, where binding with specific protein sites contributes to bioconcentration. Muscle exhibited the lowest accumulation, in which depuration half-life of UV-327 was 19.5 d. In kidney, muscle, ovary, gill, and skin, logBCF increased with increase in log K OW of the BUVSs until log K OW was ca. 6.5, above which logBCF decreased. However, the trend was not observed in the liver and intestine. Six biotransformation products were identified and mainly accumulated in the liver and intestine. Considering the nonlinear adsorption mechanism in the PBTK model, the prediction accuracy of the model was improved, highlighting the binding of xenobiotics with specific protein sites in assessing the bioconcentration of chemicals for their risk assessment.
Benzotriazoles (BTRs), benzothiazoles (BTHs), and benzotriazole UV stabilizers (BUVs) have attracted increasing attention due to their ubiquity in the environment, toxicity, and potential ecological ...risks. However, information on their distributions in the ocean is scarce. In this study, BTRs, BTHs, and BUVs were firstly determined in the surface seawater, sea-surface microlayer (SML), suspended particulate matter (SPM), and sediments of the Yellow Sea (YS) and East China Sea (ECS). The spatial distributions of BTRs, BTHs, and BUVs in the YS and ECS showed offshore decreasing trend in their concentrations, indicating that terrestrial inputs from runoff and rivers had important influences on their distributions. The organic carbon normalized partition coefficients (log Koc) of target contaminants in surface seawater-SPM (3.06-4.16 L/g) and bottom seawater-sediment (2.55-4.82 L/kg) systems were determined. SPM showed greater sorption capacities for most target contaminants than the sediment. The burial capacities of BTHs, BTRs, and BUVs from SPM to surface sediments were evaluated using their respective log Kow values and their sedimentary fluxes in the YS and ECS were quantified. BTRs, BTHs, and BUVs were enriched in the SML, with the enrichment extents of the suspended particulate phase being obviously lower than those of the dissolved phase. The ecological risks of BTRs, BTHs, and BUVs were evaluated using the risk quotient (RQ) method, which showed no toxic risk to aquatic organisms throughout the water phases, but high risk in nearshore sediments.
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•The inhibition behavior of 1H-Benzotriazole (BTA) on single and coupled copper and mild steel.•Synergistic effect of sodium molybdate and sodium phosphate with BTA.•Studying the ...effect of immersion time on persistence of protective layer.•Studying the persistence of protective layer in stagnant and flow conditions.•Good inhibition efficiency by using multicomponent inhibitor.
In this study, the corrosion inhibition of 1H-benzotriazole (BTA) alone and in combination with Na2MoO4·2H2O and Na3PO4·12H2O on single and coupled copper and mild steel in artificial sea water is evaluated. EIS and polarization results in stagnant and laminar flow conditions in different immersion times indicated that persistence of protective layer formed on single mild steel in presence of BTA is lower than that of copper, though formation of a stable protective layer on coupled copper reduced galvanic corrosion. Multicomponent inhibitor showed a better efficiency compared to BTA alone through protection of both single and coupled copper and mild steel.
