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The synthesis and isolation of [Ru(Cp)(PCy2NPh2)(=C=CHPh]PF6 and [Ru(Cp*)(PCy2NCy2)(=C=CHPh)]PF6 was successfully accomplished. Use of these ruthenium vinylidene complexes for stoichiometric reactions with a variety of amines was performed. Upon reaction with alkyl amines, deprotonation of the Cβ hydrogen resulted in formation of acetylide complex [Ru(Cp*)(PCy2NPh2)(−C≡CPh)], and the species was confirmed through independent synthesis. In contrast, reaction of the less basic aryl amine aniline with [Ru(Cp)(PCy2NCy2)(=C=CHPh)]PF6 resulted in outer sphere addition to give a Fischer carbene product. [ABSTRACT FROM AUTHOR]

This article presents a comprehensive organic chemistry experiment in which salicylaldehyde, phenylboronic acid, and aromatic amines are employed as the substrates. The selective synthesis of diarylmethyl aniline and triarylmethane could be achieved through the control of substituents. The structure of the product is characterized by ¹H NMR and 13C NMR. This experiment combines theoretical knowledge to inspire students to think about mechanisms, helps them broaden their knowledge horizons, and establishes the concept of "green chemistry" and environmental awareness. [ABSTRACT FROM AUTHOR]

Thiocyanates form an important class of organic compounds commonly found in natural products that exhibit excellent antimicrobial activity. The electrophilic thiocyanation is one of the most effective methods of introducing a -SCN functional group to the parent organic molecule. In this work, we explored an eco-friendly and highly efficient method for thiocyanation of anilines and 1-(substituted benzylidene)-2-phenylhydrazines using commercially available N-bromoscuccinimide (NBS) and potassium thiocyanate (KSCN). The optimized protocol afforded thiocyanates with good regioselectivity and excellent yields in comparison to the available methods. [ABSTRACT FROM AUTHOR]

Synthesis of heteroaryl ortho‐substituted anilines is hitherto challenging. Herein we report scope and limitation of method for annulation of 1‐(2‐nitroaryl)pyrroles and derivatives of 2‐aminobenzyl alcohol to afford ortho‐substituted pyrrolo[1,2‐a]quinoxalin‐4‐yl anilines. Reaction conditions contained elemental sulfur as promoter, while were tolerant of a wide range of aryl and heteroaryl amines. Our method would offer a feasible tactic to yield anilines steric bulk with ortho heterocyclic substituents. [ABSTRACT FROM AUTHOR]

The research focused on the photolysis of ortho‐ and para‐substituted aryl azides and the preparation of 2‐arylamino‐substituted azepines. The best results were achieved in 1,4‐dioxane for ortho‐substituted azides and in ethanol for para‐substituted azides, respectively. It was found that reactions with arylamines, which have electron‐donating groups, typically produce higher yields of heterocycles than those with electron‐withdrawing groups. [ABSTRACT FROM AUTHOR]

A simple and efficient one-pot synthetic protocol has been developed for the synthesis of 3-arylamino-2-polyhydroxyalkyl-substituted indoles by using unprotected sugars and aromatic amines. The protocol is simple to carry out with high yields under mild reaction conditions, and has atom economy with a good substrate scope and functional group tolerance, providing a new alternative route for the synthesis of structurally diverse indole derivatives. [ABSTRACT FROM AUTHOR]

Herein, we disclose a facile and efficient electrochemical method for the dibromination of aryl amines by double functionalization of aromatic C(sp2)−H (both para and ortho) under metal‐ and external oxidant‐free conditions at room temperature for the first time. The reaction is demonstrated using 1,2‐dibromoethane to dibrominate a wide range of N‐substituted aryl amines in a simple setup with C(+)/Pt(−) electrodes under mild reaction conditions. This transformation proceeds smoothly with a broad substrate scope affording the valuable and versatile N‐substituted 2,4‐dibromoanilines in moderate to excellent yields with high regioselectivity. In this paired electrolysis, cathodic reduction of 1,2‐DBE followed by anodic oxidation generates bromonium intermediates, which then couple with anilines to furnish the dibrominated products. It represents a distinctive approach to challenging redox‐neutral reactions. The versatility of the electrochemical ortho‐, para‐dibromination was reflected by unique regioselectivities for challenging aryl amines and gram‐scale electrosynthesis without the use of a stoichiometric oxidant or an activating agent. [ABSTRACT FROM AUTHOR]

The global demand for intelligent sensing of aromatic amines has consistently increased due to concerns about health and the environment. Efforts to improve material design and understand mechanisms have been made, but highly efficient non‐contact sensing with host–guest structures remains a challenge. Herein, we report the first example of non‐contact, high‐contrast sensing of aromatic amines in a hydrogen‐bonded organic framework (HOF) based on a nitro‐modified stereo building block. Direct observation of binding interactions of trapped amines is achieved, leading to charge separation‐induced emission quenching between host and guests. Non‐contact sensing of aniline and diphenylamine is realized with quenching efficiencies up to 91.7 % and 97.0 %, which shows potential for versatile applications. This work provides an inspiring avenue to engineer multifunctional HOFs via co‐crystal preparations, thus enriching applications of porous materials with explicit mechanisms. [ABSTRACT FROM AUTHOR]

In this work, we present a rapid, metal‐free and efficient method for thiocyanation of aromatic amines under microwave irradiation for the synthesis of aryl thiocyanates using inexpensive and nontoxic NH4SCN as thiocyanato source and K2S2O8 as an oxidant. This protocol tolerates a wide range of substituted anilines to provide the corresponding thiocyanated products in good to excellent yields. The features of this strategy include a broad substrate scope, high functional group tolerance, mild reaction conditions, and short reaction time. [ABSTRACT FROM AUTHOR]

6,6-Dimethyl-5,6-dihydrobenzo[f]pyrrolo[2,1-a]isoquinoline-8,9-dione and its 1-(morpholine-4-carbonyl)-substituted analog reacted with ammonia, morpholine, aniline, and naphthalen-1-amine via opening of the dioxopyrrole ring to produce enamino keto amides. The reaction conditions depended on the nucleophile nature. Ammonia and morpholine readily reacted at 20°C, whereas the reaction with aromatic amines required heating in boiling glacial acetic acid. [ABSTRACT FROM AUTHOR]

An efficient and practical one‐pot reaction for the synthesis of diarylmethyl anilines from easy available materials of salicylaldehydes, arylboronic acids and aromatic amines has been successfully developed. All the reactions proceed smoothly under transition‐metal‐free conditions via a p‐TSA promoted tandem Petasis borono‐Mannich/ nucleophilic substitution reaction, providing highly functionalized amines with wide functional groups in good to excellent yields. A reasonable explanation for this transformation was suggested. [ABSTRACT FROM AUTHOR]

Reversing the conventional site‐selectivity of C−H activation provides efficient retrosynthetic disconnections to otherwise unreactive bonds. Described herein is the Brønsted acid‐catalyzed reaction that selectively performs meta‐amination of anisidines with aliphatic‐, heterocyclic‐ and aromatic amines in a one‐pot procedure. In addition to dramatically simplifying the synthesis of meta‐substituted anilines, our approach has the advantage of the scalability and remarkable functional group tolerance, including late‐stage functionalization of pharmaceutical compounds and natural products. The control experiments and detailed computational analysis provide insight into the reaction mechanism and the origin of meta‐selectivity. The protocol extended to the synthesis of challenging tri‐aminated arenes and successfully applied for the efficient synthesis of 5‐HT6 receptor antagonists, the anti‐psychotic drugs viz.. SB‐214111, SB‐258510, and specifically, anti‐schizophrenic drug SB‐271046. [ABSTRACT FROM AUTHOR]

The self‐organization of functionalized diamines, 1‐acetyl‐1,3‐bis(haloarylamines), from three molecules of acetylene and two molecules of haloanilines in the KOH/DMSO superbase medium, has been analyzed quantum chemically in some detail in the framework of the B2PLYP(D3)/6‐311+G**//B3LYP/6‐31+G* approach. We have established that the diamines are constructed in a cascade manner via the sequential alternating additions of haloaniline anions to acetylene. The reaction sequence is catalyzed by a superbase pentacoordinated complex, KOH ⋅ 5DMSO, where the hydroxide ion is significantly separated from the potassium cation (the K−OH bond length is by 0.4–0.5 Å longer than in the bare KOH molecule). The latter imparts pronounced superbasicity to the complex and provides for a shuttle‐like proton transfer (H++OH−=H2O) during the whole cascade process. [ABSTRACT FROM AUTHOR]

2-Nitro-1H-benzo[f]chromenes reacted with alcohols to give a series of 3-alkoxy-2-nitro-2,3-dihy-dro-1H-benzo[f]chromenes as mixtures of cis and trans isomers. The reaction of 2-nitro-1H-benzo[f]chromenes with cyclic secondary amines and 3-amino-5,5-dimethylcyclohex-2-en-1-one displayed trans diastereoselec-tivity with the formation of Michael adducts with benzochroman structure. Conjugate addition of substituted anilines to the title chromenes afforded (2-hydroxynaphthalen-1-ylmethyl)-substituted β-nitroenamines. Nucleophilic dearomatization of 3-nitrobenzofurans by the action of primary aromatic amines involved aza- and retro-oxa-Michael reactions, which demonstrated a strong tendency of 3-nitrobenzofurans to undergo opening of the furan ring. [ABSTRACT FROM AUTHOR]

The bio-oxidation of a series of aromatic amines catalyzed by T. versicolor laccase has been investigated exploiting either commercially available nitrogenous substrates [(E)-4-vinyl aniline and diphenyl amine] or ad hoc synthetized ones [(E)-4-styrylaniline, (E)-4-(prop-1-en-1-yl)aniline and (E)-4-(((4-methoxyphenyl)imino)methyl)phenol]. At variance to their phenolic equivalents, the investigated aromatic amines were not converted into the expected cyclic dimeric structures under T. versicolor catalysis. The formation of complex oligomeric/polymeric or decomposition by-products was mainly observed, with the exception of the isolation of two interesting but unexpected chemical skeletons. Specifically, the biooxidation of diphenylamine resulted in an oxygenated quinone-like product, while, to our surprise, in the presence of T. versicolor laccase (E)-4-vinyl aniline was converted into a 1,2-substited cyclobutane ring. To the best of our knowledge, this is the first example of an enzymatically triggered [2 + 2] olefin cycloaddition. Possible reaction mechanisms to explain the formation of these products are also reported. [ABSTRACT FROM AUTHOR]

The Pd-catalyzed highly selective synthesis of mono- and di-2-fluoroallylic amines from gem-difluorocyclopropanes and ubiquitous unprotected primary anilines is herein described. Initial kinetic investigations suggest a first order in the gem-difluorocyclopropane substrate, as well as a circa zeroth order in the aniline coupling partner. The newly produced fluoroallylic motifs should find important applications in synthetic as well as medicinal chemistry and stimulate the further development of coupling methods based on strained cyclic building blocks. [ABSTRACT FROM AUTHOR]

A base‐mediated protocol has been established for the N‐acetylation of anilines/amines at room temperature. Reaction utilizes acetonitrile as a solvent as well as a surrogate of the acetyl group. Apart from acetonitrile, trifluoroacetonitrile could also be utilized in the reaction. The advantages of the reactions are simple operation, transition‐metal‐free approach, short reaction time, high functional group tolerance, and gram‐scale synthesis, which show the reaction's utility. The developed strategy represents a valuable approach in synthetic organic chemistry. [ABSTRACT FROM AUTHOR]

A metal catalyst free approach for regioselective ortho-chlorination of anilines has been developed using a secondary amine as the organocatalyst and sulfuryl chloride as the halogen source under mild conditions. A wide range of substrates were compatible with this catalytic system. In addition, this catalytic protocol has been applied to the efficient synthesis of bioactive compounds and modification of drug derivatives. Further studies indicated that the anionic trichloride species was responsible for the ortho-selectivity. [ABSTRACT FROM AUTHOR]

An electrosynthetic approach was developed for the oxidative C–H/N–H cross-coupling amination of cyclic sulfamidate imines under undivided electrolytic conditions via an atom- and step-economic method. In this transformation, a wide variety of cyclic or acyclic dialkyl amines, amino acid derivatives, and more challenging primary anilines acted as suitable substrates with good reaction outcomes. The synthetic advantage of this electrochemical method is augmented by high functional group compatibility (86 examples), ease of scale-up to gram scale, and accomplishment of late-stage functionalization of complex biologically relevant molecules, which provides an efficient tool with broad potential application prospects in medicinal and synthesis chemistry. Mechanistic studies reveal that this transformation probably occurred through a radical process. [ABSTRACT FROM AUTHOR]

The reaction of hexamethylene diisocyanate with some aliphatic, aromatic and heterocyclic amines was studied. The effect of the amine nature on the reaction time was discussed. The effect of the position of a substituent in the aromatic ring on the reactivity of anilines upon reaction with hexamethylene diisocyanate was shown. [ABSTRACT FROM AUTHOR]

Aryl amines are synthesized from halobenzenes via copper mediated reactions employing sodium azide under mild conditions in ethanol/water. The reaction proceeds stepwise via the aryl azide, which is reduced to the corresponding amine in‐situ. The methodology allows syntheses of amines from corresponding para‐, meta‐ and ortho‐bromobenzenes bearing electron withdrawing groups. Bifunctional halobenzenes bearing alkanoyl chains with terminal bromides are selectively transformed, generating an aniline and an aliphatic azide, as this azide position is stable to reduction. A one‐pot multistep sequence for preparation of the target amines was designed. The azide formation is mediated by CuI while elemental Cu is generated simultaneously, which is deposited onto the employed PTFE stirring bar used in the reaction. The Cu films were quantified and analysed by SEM/EDS. The Cu, either deposited or in solution, is responsible for the azide reduction, possibly involving nitrene intermediates. An application of the modified stirring bars as a heterogeneous catalyst for a click reaction is demonstrated. [ABSTRACT FROM AUTHOR]

Transamidation of weakly nucleophilic aromatic amines is achieved under melt conditions and in absence of catalyst, activating agent, base, and solvent. Chemoselectivity of the protocol is demonstrated with transamidation of aniline‐bearing protic carboxylic acid group and wide range of anilines. Broad applicability of the process is demonstrated with the synthesis of bioactive natural product amide, Avenanthranamide‐A. By‐product was isolated for re‐use in synthesis of starting amide, manifests atom economy, and sustainability of the protocol. Thus, our findings imply that the developed protocol is environmentally benign, operationally simple yet versatile for protection‐deprotection free synthesis of amides, peptides and amide‐based drugs. [ABSTRACT FROM AUTHOR]

Novel 2‐perfluoroalkylmethyl,4‐arylamino substituted tetrahydroquinolines (THQ) were expeditiously synthesized from perfluoroalkyl iodides RF−I and monosubstituted anilines. First, radical bis‐addition of vinyl acetate on RF−I afforded gem‐iodoacetoxy derivatives (newly characterized by NMR and MS) being actually masked/activated aldol synthons. Their reaction in 1 : 4 ratio with arylamines afforded title THQ under mild conditions in good yields (60–95 %) and diastereoselectivities (65 : 35–95 : 5 cis/trans isomer ratio); m‐substituted anilines regiospecifically lead to 7‐substituted THQ. Mechanistic investigation suggested the THQ formation to proceed through Michael then imine addition of two aniline units on an RF‐substituted crotonaldehyde intermediate, then through the cyclization of the resulting bis(arylamino/imino) intermediate through electrophilic aromatic substitution. Various RF (C6, C2, C4) and arylamine substitutions (p‐,o‐,m‐ alkyl, alkoxyl, halogen...) were thus exemplified. [ABSTRACT FROM AUTHOR]

Aniline (C 6 H 5 NH 2) is one of the hazardous aromatic amine where an amino group -NH 2) is connected to phenyl ring (C 6 H 5). Based on the evaluation of the 96-hour LC 50 of aniline, two sublethal concentrations (4.19 mg/l and 8.39 mg/l) were selected for acute exposure tests in freshwater fish Channa punctatus. The liver, gills and kidney of fish being the principal sites of xenobiotic material accumulation, respiration, biotransformation, and excretion are the focus of the present study. Throughout the exposure time, the comet assay revealed increased tail length and tail DNA percentage indicating maximum damage to liver, gills and kidney of treated group after 96 h. After acute exposure, there was a significant (p ≤ 0.05) increase in the enzymatic activity of glutathione-S-transferase (GST) and acetylcholinesterase (AChE), whereas decline in superoxide dismutase (SOD) and catalase (CAT) activity was observed. Meanwhile, levels of malondialdehyde (MDA) increased over the exposure period for both concentrations. After 96 h of exposure, degree of tissue change (DTC) was evaluated in liver, gill and kidney of aniline exposed fish. Additionally, light microscopy revealed multiple abnormalities in liver, gills and kidney of all the treated groups. Significant changes were observed in the levels of biochemical markers viz., glucose, triglyceride, cholesterol, aspartate transaminase, alanine transaminase and urea following a 96-hour exposure to aniline. Studies using ATR-FTIR and transmission electron microscopy (TEM) revealed changes in biomolecules and structural abnormalities in several tissues of the aniline-exposed groups in comparison to the control group respectively. [Display omitted] • Aniline exposure induces DNA damage in different organs of test animal. • Aniline exposure caused oxidative stress via alterations in CAT, SOD, GST and AChE activity. • Histopathological alterations were observed by light microscopy and TEM. • ATR-FTIR studies suggested alterations at bio-molecular level. [ABSTRACT FROM AUTHOR]

In situ Raman spectroscopy was used for the first time to study the reaction intermediates/products of the oxidative polymerization of aniline to polyaniline (PANI) with peroxydisulfate in aqueous solutions of different initial acidity. Raman spectra were recorded for the drops of reaction mixture taken at various reaction times. Five reaction systems with different pH of the monomer solution (pH mon), leading to 1-D nanostructured PANIs (pH mon =5.8, 4.6 and 4.5) and granular PANIs (pH mon = 3.4 and 1.0) were explored. Spectral characteristics of different reaction phases - athermal, exothermic and post-propagation were identified and correlated with the proposed mechanisms of aniline polymerization and nanostructures formation. For the nanostructured PANIs, the athermal phase was characterized by pronounced strengthening of the δ(N−H)/ν(C N) Q band at 1510–1520 cm−1, while the characteristic of the second exothermic phase was the strengthening of the ν(C∼C) B /ν(C∼C) Phz band at c.a. 1636 cm−1 which becomes stronger than the ν(C C) Q /ν(C∼C) SQ band at c.a. 1590 cm–1. For granular PANIs, the band at 1590 cm–1 was stronger than that at 1630 cm–1 for all reaction phases. For all reaction systems, characteristic feature of the post-propagation phase was strengthening of the ν(C∼N+•) band at 1330–1340 cm−1 due to delocalized polarons. For granular PANIs, the band associated with phenazine-like units at c.a. 1415 cm−1 disappeared after the exothermic phase, while for nanostructured PANIs it was seen until the end of the reaction. The obtained results are expected to be useful in further investigations of the intermediates/products and mechanisms of polymerizations of other aromatic amines. • The oxidative polymerization of aniline in media of different initial acidity leading to 1-D nanostructured and granular polyanilines (PANIs) was studied by i n situ Raman spectroscopy. • Spectral characteristics of the individual reaction phases athermal, exothermic and post-propagation, were identified. • For nanostructured PANIs the bands at c.a. 1510 cm−1 and 1636 cm−1 showed pronounced strengthening during the athermal and second exothermic phases, respectively. • For nanostructured PANIs the band at c.a. 1636 cm−1 becomes stronger than that at c.a. 1590 cm–1 during the second exothermic phase while inverse intensity ratio characterizes the other phases. • For granular PANIs the band at c.a. 1590 cm–1 is stronger than the band c.a. 1636 cm−1 for all reaction phases. [ABSTRACT FROM AUTHOR]

Two perfluorinated compounds (PFCs) and 17 different primary aromatic amines (PAAs) were analyzed by liquid chromatography–tandem mass spectrometry (LC–MS/MS) in migrants from 35 cookware samples marketed in Turkey. Among PFCs, only PFOA was identified in 6 samples. Only two components among PAAs, namely aniline (ANL) and 4,4′-methylenedianiline (4,4′-MDA), were detected in analyzed samples. Although aniline was detected in all samples, 4,4′-MDA was detected in only 4 samples. The effects of simulant volume, temperature, and repeated use on the release of these migrants from non-stick cookware were investigated. Three simulant volumes (200, 500, and 1000 mL) were used in migration tests. PFCs and PAAs were identified in simulants at 200 and 500 mL. The increase in the amount of simulant caused a decrease in the concentration of these migrants. The lowest migration values were observed in the samples at consecutive usage cycles. PFCs and PAAs exhibited the highest migration ability with increasing temperature. [ABSTRACT FROM AUTHOR]

Embedded pellets obtained by means of embedding activated sludge in polyvinyl alcohol—sodium alginate were successfully adapted in aniline wastewater degradation system. The results of shake flask experiment showed that the combination of sludge and embedded pellets had the best performance in degrading aniline, compared with sludge system and pellet system. Moreover, the application of embedded pellets promoted the toxicity tolerance and operation performance of the reactor. The enhanced reactor could completely degrade aniline and ammonia nitrogen in 150 and 240 min, and the total nitrogen removal rate increased by 26.83%. Meanwhile, high-throughput sequencing results illustrated that the addition of embedded pellets can effectively protect the diversity of functional microbial community. The average relative abundances of main functional genera such as Hydrogenophaga (aromatic amine compounds degradation and heterotrophic nitrification-aerobic denitrification), Norank_f__ Microscillaceae (nitrification), Brevundimonas (heterotrophic nitrification-aerobic denitrification), and Flavobacterium (denitrification) increased by 50.63%, 73.45%, 99.71%, 89.6%, 72.01%, and 95.70%, respectively. [ABSTRACT FROM AUTHOR]

Several primary aromatic amines (AAs) are known or suspected carcinogens. Despite this, the exposure of pet animals to this class of chemicals is unknown. In this study, we investigated the occurrence of 30 AAs and two tobacco chemical markers (nicotine and cotinine) in 63 pet urine (42 dog and 21 cat) and 77 pet feces (37 dog and 40 cat) samples collected from the Albany area of New York State. Eight of the 30 AAs (∑8AAs) were found in > 38% of dog and cat urine samples, at median concentrations of 7.99 (range: 0.42–52.3 ng/mL) and 31.4 (2.63–75.9) ng/mL, respectively. Nine of the 30 AAs (∑9AAs) were found in > 73% of dog and cat feces samples, at median concentrations of 278 (range: 61.7–613 ng/g) and 240 (55.4–645) ng/g dry wt, respectively. Among the 30 AAs, 2,6-dimethylaniline (2,6-DMA) accounted for the highest median concentrations in both urine and fecal samples. Median concentrations of nicotine and cotinine were below 0.92 ng/mL in urine and below 3.86 ng/g in feces of both dogs and cats. No significant relationship was found between AA concentrations and pet age or gender. The lack of significant Spearman’s rank correlation between the concentrations of AA and nicotine in pet urine/feces suggested that sources other than tobacco smoke contributed to AA exposure in pets. Furthermore, the calculated fecal excretion rates of AAs were higher than the intake rates (estimated through reverse dosimetry), which indicates that cats and dogs are exposed to AA precursors such as azo dyes. Concentrations in urine and feces reflected exposure to direct and indirect exposure sources, respectively, of AAs.

Anilines are key constituents in biologically active compounds and often obtained from transition metal‐catalyzed coupling of an aryl halide with an amine. In this work, we report a transition metal‐free method for the synthesis of meta‐bromo‐ and meta‐trifluoromethylanilines starting from 3‐tribromomethylcyclopentanone or 3‐(2‐bromo‐2‐chloro‐1,1,1‐trifluoroethyl)cyclopentanone, respectively. The scope of the transformation is shown by application of primary, secondary and aromatic amines. The reaction proceeds in acceptable to high yields (20–81 %), and allows for the synthesis of anilines with substitution patterns otherwise difficult to access. [ABSTRACT FROM AUTHOR]

Although primary aromatic amines (AAs) are widely used in consumer products, little is known about their occurrence in indoor dust. A liquid chromatography – tandem mass spectrometry (LC-MS/MS) method was applied for the determination of 29 AAs and two tobacco smoke markers (nicotine and cotinine) in 256 house dust samples collected from 10 countries. Of the 29 AAs analyzed, p-anisidine, o-anisidine, 2,6-dimethylaniline (2,6-DMA), p-cresidine (p-CD), p-toluidine (p-TD), 4,4′-methylenedianiline (4,4′-MDA), ortho/meta-toluidine (o/m-TD), 4-chloroaniline (4-CA), 2,4-diaminotoluene (2,4-DAT), aniline, and 2-naphthylamine (2-NA) as well as nicotine and cotinine, were found prevalent in house dust samples. Sum median concentrations of AAs and tobacco smoke markers varied from 29.6 to 576 ng/g (overall median: 200 ng/g) and 10.8 to 2920 ng/g (415 ng/g), respectively. Among AAs, aniline was the abundant contaminant, found at median concentrations ranging from 19.6 ng/g (Colombia) to 334 ng/g (South Korea). Nicotine was detected in all indoor samples at median concentrations ranging from 9.92 ng/g (Colombia) to 2790 ng/g (India) ng/g. Concentrations of AAs in indoor dust were significantly correlated with those of nicotine. Estimated daily intake (EDI) of select AAs through the ingestion of house dust was in the range of 0.019–3.03 ng/kg-bw/day, which was five orders of magnitude below the tolerance limits.

Aniline and N-methylaniline are common contaminants in commercially produced indigo. It is known, that commercially produced indigo contains up to 0.6% aniline and 0.4% N-methylaniline by weight and indigo dye shows a small mutagenic effect, most probably due to the presence of these contaminants. The present work describes a new and powerful analytical method to determine the concentration of these contaminants in indigo. This method is based on the transformation of water insoluble indigo into soluble leucoindigo and allows therefore the acidic extraction of the aromatic contaminants. This transformation step is essential, because the main part of these contaminants are strongly included in the indigo crystals. The amount of extracted aniline and N-methylaniline from the leucoindigo solution was quantified with high performance liquid chromatography (HPLC, combined with a photo diode array detector). A possible accumulation of the aromatic amines at the indigo crystal surface was investigated using FTIR and by adsorption studies. Therefore this method allows an accurate monitoring of these toxic by-products in the indigo dye, which is important for an economic and environmental assessment of the denim production. [ABSTRACT FROM AUTHOR]

Substituted undecahydrido-closo-dodecaborates [B12H11NR2]2− have potential use in materials and drugs, but have presented a synthetic challenge. Microwave-assisted palladium-catalyzed amination of iodo-dodecaborate [B12H11I]2− allows mild and reproducible formation of B–N bonds with aromatic amines, HN-containing heteroaromatics, and amides. The reaction allows general access to amides, reproducible reactions to dodecaborate-substituted anilines, and, for the first time, the substitution of dodecaborate with HN-containing heterocycles. [ABSTRACT FROM AUTHOR]

Purpose: Nine bladder cancer (BCa) cases were reported among aromatic amine-exposed male workers at a factory manufacturing organic dye/pigment intermediates in Japan. We aimed to evaluate the characteristics of aromatic amine-exposed workers by cross-sectional observation, and the risk of BCa by assessing the standardized incidence ratio (SIR). Methods: In the cross-sectional study, our subjects were: 9 BCa patients, 36 aromatic amine-exposed non-patients, and 79 non-exposed workers from 3 factories. We evaluated the subjects' medical history, urinalysis, qualitative determination of nuclear matrix protein 22, and urinary cytology. For SIR assessment, 98 aromatic amine-exposed workers from 1 factory were included, and the Japanese general male population was used as a referent population. Since no direct aromatic amine-exposure data were available, we calculated surrogate exposure levels using information on job sites, exposure potency, and duration. Results: Coexistent aromatic amines were ortho-toluidine (OT), aniline, para-toluidine, ortho-anisidine, 2,4-xylidine, and ortho-chloroaniline. The prevalence rates of cystitis and bladder lesion-related symptoms in both BCa patients and aromatic amine-exposed non-patient workers were significantly higher than those of non-exposed workers. Overall, the SIR for BCa in OT-exposed workers was 56.8 (95% CI 27.7–104.3) and apparent dose–response relationships were revealed between the SIR and the surrogate exposure level in the 0–10-year lagged analyses. Overall, SIRs in other aromatic amine-exposed workers were also significantly high but no or unclear dose–response relationships were observed. Conclusions: We conclude that OT may be responsible for the increased risk of BCa. Regular monitoring of bladder lesion-related symptoms is essential for the early identification of BCa. [ABSTRACT FROM AUTHOR]

A general procedure for the synthesis of ethyl Z-3-halo-3-nitroacrylates by the reaction of ethyl 3-nitroacrylate with Cl2 or Br2 followed by dehydrohalogenation was proposed. Ethyl Z-3-chloro-3-nitroacrylate was obtained for the first time. The reaction of halonitroacrylates with anilines followed the pathway of the formation of aza-Michael adducts, the dehydrohalogenation of which led to new β-nitro enamines, namely, ethyl Z-2-arylamino-3-nitroacrylates. [ABSTRACT FROM AUTHOR]

Ammonia and cyclic aromatic compounds are principal products from combustion of various fractions of biomass. Yet, kinetic mechanistic models on formation of NO x from biomass de-couple the oxidation mechanism of ammonia from that of aromatic molecules. Literature kinetic models do not consider a plausible formation of aniline as the initial product from the interaction of amine radicals and benzene molecules (as the simplest aromatic molecule). Such reaction acts a sink for NH 2 radicals, and thus may alter the yields of NO x and HCN. To fill in this gap, this study reports production pathways of aniline from NH 2 + benzene reactions, maps out unimolecular decomposition pathways of aniline and its derived anilino radical into, and explores the effect of the title reaction on the yields of small nitrogenated species from co-combustion of ammonia and benzene. We find that anilino radical to preferentially decompose into iso -HNC and a cyclopentadienyl radical. The resonance-stabilized structure of the anilino radical enables it to undergo bimolecular reaction with the aniline molecule to generate N-analogous compounds of dioxins, namely diphenylamine, carbazole, and phenazine. Detail kinetic modeling discloses that decomposition of aniline initiates at 1100 K with ammonia and HCN signify the most abundant N-bearing species at intermediates and high temperatures, respectively. Introducing the newly constructed aniline sub-mechanism in NO x + benzene kinetic model from the literature (i.e., CERCK model) alters predicted concentrations of principal N species within factors of 1.2- 2 between 1100–1300 K. It is hoped that reaction rate constants and mechanistic pathways presented herein to improve the predictive performance of kinetic models that address NO x and HCN emission from flames of ammonia and aromatic-containing fuels in general. [ABSTRACT FROM AUTHOR]

N -Aryl-1,2,3,4-tetrahydroisoquinolines are obtained via a convenient and short protocol with a broad range of substituents on both aromatic rings and high functional group tolerance. Starting from readily available ortho -brominated aromatic aldehydes and primary aromatic amines, condensation of these building blocks under reductive conditions gives N -aryl 2-bromobenzylamines. The C-3/C-4-unit of the tetrahydroisoquinoline is introduced using commercially available 2-ethoxyvinyl pinacolboronate under Suzuki conditions. Finally, the obtained crude ortho -ethoxyvinyl benzylamines are cyclized via an intramolecular reductive amination using the combination of triethylsilane/TFA to give the desired N -aryl-1,2,3,4-tetrahydroisoquinolines. [ABSTRACT FROM AUTHOR]

[Display omitted] • Phenolic hydroxyl-functionalized hyper-cross-linked polymers were synthesized according to two-step Friedel-Crafts alkylation reactions. • The polymers contained high specific surface area and hierarchical porosity. • 1,4-bis(chloromethyl)benzene was the super crosslinking agent to increase the S BET (1282 m2/g) of polymers. • In aqueous solution, HCPS-BNAP-FDA was expected to adsorb p-nitroaniline with the q max of 277.30 mg/g. • In organic solution, HCPS-BNAP-FDA was expected to adsorb aniline with the q max of 202.38 mg/g. Herein, three phenolic hydroxyl-modified hyper-crosslinked polymers were synthesized according to two-step Friedel-Crafts alkylation, and they were applied to adsorb small aromatic amines in aqueous and organic solvents. The first low-temperature Friedel-Crafts at 313 K introduced massive phenolic –OH to the intermediates, then the second high-temperature Friedel-Crafts at 353 K, also known as post-crosslinking reaction, brought a hyper-crosslinked skeleton composed of plentiful rigid methylene bridges to the target products, greatly enhancing the Brunauer-Emmett-Teller (BET) surface area (S BET) and total pore volume (V total) of the polymers. I n aqueous solution, the HCPS-BNAP-FDA had great potential for efficient adsorption of aniline and p-nitroaniline (p-NANL), and the Langmuir model predicted that their maximum capacities (q max) were 209.25 mg/g and 277.30 mg/g, respectively. In cyclohexane solution, the q max of aniline on HCPS-BNAP-FDA was predicted to be 202.38 mg/g. The removal aniline in aqueous solution could exceed 95 % when the original concentration was less than 200 mg/L, and the final concentration was 0.12 mg/L, much lower than the emission limit of China (GB 4287–2012, China). The polymer with 1,4-bis(chloromethyl)benzene (DCX) as crosslinking agent had the highest S BET (1282 m2/g) and the best adsorption performance for aniline (q max , 258.73 mg/g). The adsorption mechanism demonstrated that the grafting of phenolic –OH groups improved the adsorption performance, as the possible hydrogen bonds and acid-base interactions. The micropores added via post-crosslinking also achieved a significant increase in adsorption capacity, that is, the pore filling adsorption mechanism. [ABSTRACT FROM AUTHOR]

A convenient synthesis of 4‐trifluoromethyl‐quinolines from 1‐trifluoromethyl‐prop‐2‐yne 1‐iminium triflates and anilines in a one‐pot two‐step Michael addition/intramolecular cyclization sequence is reported. With ring‐substituted anilines, a wide range of 4‐CF3‐quinolines bearing additional substituents and functional groups in the C‐2, C‐6, and C‐8 positions were prepared, mostly in high yields. Even a 4‐CF3‐5‐Me‐quinoline could be obtained. From mono‐Boc protected 1,4‐ and 1,3‐phenylenediamine, 2‐aryl‐substituted 6‐amino‐4‐CF3‐quinoline and 7‐amino‐4‐CF3‐quinoline, respectively, were prepared. 4‐CF3‐benzo[h]quinolines were obtained from the mentioned acetylenic iminium salts and 1‐naphthylamine. With N‐monosubstituted aromatic amines such as N‐methylaniline and 1,2,3,4‐tetrahydroquinoline, N‐substituted 4‐CF3‐quinolinium salts and pyrrolo[1,2‐a:3,4‐c']diquinoline derivatives bearing two CF3 substituents could be prepared. [ABSTRACT FROM AUTHOR]

An efficient and selective benzylic C(sp3)–H addition of o-CH3-substituted tertiary aromatic amines to alkenes has been achieved using an anilido-oxazoline ligand supported scandium catalyst, which provides an atom-economic method for the synthesis of a new family of alkylated tertiary anilines. A wide range of amine and alkene substrates are compatible with the catalyst system. [ABSTRACT FROM AUTHOR]

Here we describe the reaction of dimethyl acetylenedicarboxylate with aniline, N‐ethylaniline or diphenylamine. The diasteromeric enamines obtained in each case are inequivocally characterized by 1H‐ and 13C‐NMR spectra and computational methods. The heterocyclization reaction of each isolated diasteromeric enamines, leads to different products depending on the reaction conditions and the stereoelectronic characteristics of the substrate. Thus, we were able to obtain 1‐phenyl‐2‐methoxycarbonyl‐4‐quinolinone, and to find a new route for obtaining 1‐phenyl‐3‐oxo‐1,3‐dihydro‐2‐indoliliden‐acetic acid derivatives. [ABSTRACT FROM AUTHOR]

We successfully added bamboo and glass fibers into bisphenol A-aniline based benzoxazine (BA-a) resin by hot-pressing method. In order to improve the interfacial adhesion between bamboo fibers and the matrix, bamboo fibers were pretreated in 6 wt% NaOH solutions for 12 h. The results showed alkali-treatment had a positive effect on mechanical properties of the composites at both room and elevated temperatures (60[degrees]C, 110[degrees]C, 160 C, and 210[degrees]C). Due to the incorporation of glass fibers, the bamboo/glass reinforced-polybenzoxazine hybrid composites exhibited highest strength and modulus among all samples and had high residual mechanical properties at elevated temperatures (residual mechanical properties refers to the ratio of strength and modulus of the composites at elevated temperatures to that measured at room temperature). The fractured surface morphologies of the composites were observed by scanning electron microscope. The results showed with the increase of temperature, the debonding and fiber pull-out became apparent, and the matrix softening could be clearly observed at 210[degrees]C. In addition, thermal and thermomechanical properties of neat benzoxazine and the composites were also investigated through thermogravimetric analysis and dynamic mechanical analyzer, respectively., INTRODUCTION In the fields of aerospace, architecture and automobile, fiber reinforced polymer composites have been widely applied in the past few decades due to their excellent properties such as light [...]

Copper(II) complexes carrying pyridylmethyleneaminobenzoate or -propanoate ligands, LCuX, were prepared in one-pot reactions from pyridinecarboxaldehyde, aminobenzoic acid or [beta]-alanine, and Cu[X.sub.2] (X = Cl, N[O.sub.3], OAc, or OTf). All complexes were characterized by single-crystal X-ray diffraction studies and formed either dimers, tetramers, or coordination polymers. Attempted preparation of the respective alkoxide complexes, LCu(OR), was unsuccessful, but use of LCuX/NaOMe mixtures in rac-lactide polymerization indicated under some conditions coordination-insertion polymerization via a copper alkoxide as the mechanism. The complexes performed poorly in rac-lactide polymerization, showing low activities (12 h to completion at 140 [degrees]C), low to moderate heterotacticity ([P.sub.r] = 0.6-0.8), and poor polymer molecular weight control (intramolecular transesterification). They were competent catalysts for Chan-Evans-Lam couplings with phenylboronic acid, without any indication of side reactions such as deboration or aryl homocoupling. The complexes were active in undried methanol, without addition of base, ligand, or molecular sieves. Aniline, n-octylamine, and cyclohexylamine were coupled quantitatively under identical reaction conditions. There is only little influence of the anion on activities (less than a factor of 2) but a strong influence on induction periods. The complexes were not active in CEL coupling with alcohols, phenols, or alkylboronic acids. Key words: copper complexes, homogenous catalysis, Chan-Evans-Lam coupling, lactide polymerization, mechanism. Nous avons prepare des complexes de cuivre(II) de formule LCuX portant des ligands pyridylmethyleneaminobenzoate ou -propanoate par reactions en recipient unique entre le pyridinecarboxaldehyde et l'acide aminobenzoique ou la b-alanine, en presence de Cu[X.sub.2] (X = Cl, N[O.sub.3], OAc ou OTf). Tous les complexes ont ete caracterises par diffraction des rayons X sur monocristal et se presentaient sous forme soit de dimeres, de tetrameres ou de polymeres de coordination. Les tentatives de preparation des complexes d'alcoolate correspondants, de formule LCu(OR), ont echoue. Cependant, l'utilisation de melanges de LCuX/NaOMe pour la polymerisation du rac-lactide indiquait, dans certaines conditions, une polymerisation de type coordination-insertion dont le mecanisme ferait intervenir un alcoolate de cuivre comme intermediaire. Les complexes ont produit de pietres resultats pour effectuer la polymerisation du rac-lactide, presentant une faible activite (12 h pour une reaction complete a 140 [degré]C), un heterotacticite faible a moderee ([P.sub.r] = 0,6-0,8) et offrant un faible controle sur le poids moleculaire du polymere (transesterification intrmoleculaire). Cependant, ils se sont reveles aptes a catalyser des couplages de Chan-Evans-Lam avec l'acide phenylboronique, et ce, sans aucun signe de reaction secondaire telle que la deboration ou l'homocouplage d'aryles. Les complexes etaient actifs dans le methanol non asseche, sans base, ligand ou tamis moleculaires ajoutes. L'aniline, la n-octylamine et la cyclohexylamine ont procede au couplage de maniere quantitative dans les memes conditions reactionnelles. L'anion n'exerce que peu d'influence sur l'activite (par un facteur inferieur a 2), mais exerce une forte influence sur la periode d'induction. Les complexes se sont reveles inactifs dans le couplage de Chan-Evans-Lam avec des alcools, des phenols ou des acides alkylboroniques. [Traduit par la Redaction] Mots-cles : complexes de cuivre, catalyse homogene, couplage de Chan-Evans-Lam, polymerisation de lactide, mecanisme., Introduction Copper has found widespread use in catalytic transformations, (1,2) but its application in polymerization catalysis has caused some controversy. It has been widely employed in radical polymerizations involving a [...]

Herein we report the use of a soluble polymer support PEG-2000 on Pd-catalyzed reactions to improve the functionalization of aromatic amines and the synthesis of N-heterocycles. Compatibility of metal-catalyzed reactions for assembling privileged structures such as functionalized anilines were studied. PEG-supported anilines were found to be suitable substrates for Pd-catalyzed N-arylation, Sonogashira and Heck reactions. PEGylated substrates were prepared in yields up to 94%. This work consists on a proof of concept on the use of PEGylated anilines on Pd-catalyzed cross-coupling reactions. Indole core was attained in 82% and 62% yields, via two different routes. [ABSTRACT FROM AUTHOR]

• Aromatic amines namely aniline and o-phenylenediamine capped TiO 2 was synthesized. • The life time of o-phenylenediamine/TiO 2 (T-2) composite was measured as 9.8 ms. • Photo-conversion efficiency of T-2 composite was found to be 9.84%. In this work, the efficiency of dye-sensitized solar cells (DSSC) was improved by capping TiO 2 with simple aromatic amines as a complexing agent. The aromatic amines, aniline and o-phenylenediamine capped TiO 2 composites were synthesized via hydrothermal route and used as scattering layer in dye-sensitized solar cell (DSSC). Markedly, the maximum photo-conversion efficiency of 9.84% was achieved with o-phenylenediamine capped-TiO 2 composite as o-phenylenediamine capped-TiO 2 showed higher reflectivity than the pristine TiO 2 , which is highly beneficial for reflecting the photons back to photoanode. In addition, the average life time of carriers in o-phenylenediamine capped-TiO 2 was found to be 9.8 ms, which was 2 times higher than the pristine TiO 2 (4.29 ms). [ABSTRACT FROM AUTHOR]

A radical path for the conversion of o-substituted arylamines to o-phenylenediimine derivatives is reported. In the presence of [RuII(PPh3)3Cl2] (RuP), 2-(phenylthio)aniline (LSNH2) acts as an o-amination agent. Reaction of LSNH2 with RuP in toluene promotes (4e + 4H+) oxidative dimerization affording an o-phenylenediimine complex of ruthenium(II). Similarly, intermolecular coupling between LSNH2 and other arylamines has been achieved. [ABSTRACT FROM AUTHOR]

Benzynes were selectively generated in situ from phenols and trapped regioselectively with potassium hexamethyldisilazide to form primary anilines following acidic workup. The direct conversion of a phenolic hydroxyl group into a free amino group is a useful method for the preparation of primary aryl amines that are hard to synthesize by using coupling reactions involving phenol derivatives with ammonia. Whereas reactions of ortho‐ and meta‐substituted phenols produced meta‐substituted anilines exclusively, those of para‐substituted phenols provided ortho‐silylanilines. [ABSTRACT FROM AUTHOR]

A new, general ortho/para-selective anodic dehydrogenative cross-coupling of two aryl amines, naphthalen-2-amine derivatives and anilines, is described. This electrochemical protocol assembles a wide range of unsymmetrical biaryls in good to excellent yields under mild, additional-metal-catalyst-free, oxidant-free conditions with excellent selectivity, broad substrate scope, and wide functional group tolerance. This electrochemical technology is highlighted with facile incorporation of important pharmacophores into the resulting biaryls, and is applicable to the homocoupling of anilines for producing symmetrical biaryls. [ABSTRACT FROM AUTHOR]

Graphite oxide (GO) exhibits selective sorption of di -butylamine from a mixture of butylamine, di- butylamine and tri -butylamine. The selectivity is attributed to the higher basicity of di -butylamine in comparison to butylamine and tri -butylamine. Reaction of GO with a mixture of hexylamine and cyclohexylamine, two amines of similar basicity but different structures, suggests that in alkylamines, selectivity is predominantly due to the basicity of the amine with structural differences playing almost no role. However, when GO reacts with a mixture of aniline and cyclohexylamine (amines with a large difference in basicity) no selectivity is observed. The π-π interaction between the aromatic amine, aniline, and the aromatic regions of GO causes the sorption of aniline in its non-protonated form as much as cyclohexylamine with a far higher basicity. Image 10702 [ABSTRACT FROM AUTHOR]

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Nanocomposites of polyaniline with some rare earth chlorides like neodymium chloride, europium chloride, and dysprosium chloride were synthesized by chemical oxidative polymerization of aniline. Morphological, structural, thermal, optical, magnetic, and electrical properties of the samples were characterized by scanning electron microscope, x-ray diffractometer, Fourier transform infrared spectrometer, thermogravimetric analyzer, differentiating scanning calorimeter, optical absorption spectroscopy, room temperature magnetic susceptibility measurement, and low temperature electrical transport measurement. Nanocomposites were thermally more stable than pure polyaniline and they were more crystalline than pure polyaniline. Magnetic susceptibilities of the samples were field dependent. Three-dimensional variable range hopping charge transport mechanism was followed by the samples. The dc magnetoconductivity of the composites can be explained in terms of forward interference effect and wave function shrinkage effect. dc conductivity of Europium chloride-polyaniline composite shows a transition from forward interference model to wave function shrinkage model. Ac conductivity of the investigated samples can be explained in terms of correlated barrier hopping model. Permittivity of the sample is dominated by the grain boundary behavior in low frequency and by the grain phase in the high frequency and frequency dependence of real part of impedance is explained by Maxwell-Wagner capacitor model. [ABSTRACT FROM AUTHOR]