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Metal‐free Friedel–Crafts benzylation (FCB) of scarcely reactive arenes and heteroarenes was performed under on‐water conditions by an environmentally sustainable procedure. The catalytic strategy exploits the hydrophobicity of the resorcinarene macrocycle 1 a. The proposed mechanism is based on the activation of benzyl chloride by H‐bonding interactions with catalyst 1 a. In fact, under on‐water conditions the hydrophobic amplification of the strength of the H‐bonding interactions between the OH groups of the resorcinarene catalyst and the chlorine atom of benzyl chloride leads to polarization of the C−Cl bond, which consequently promotes electrophilic attack of the π nucleophile. Thus, many arenes and heteroarenes were efficiently benzylated under mild on‐water conditions by using resorcinarene 1 a as catalyst. The FCB of benzene is industrially relevant for the synthesis of diphenylmethane, and hence the on‐water procedure was extended to the gram‐scale synthesis of diphenylmethane, starting from benzene and benzyl chloride in the presence of resorcinarene catalyst 1 a. [ABSTRACT FROM AUTHOR]

The covalently functionalized cellulose nanocrystal (CNC) composites were synthesized by bonding common bactericides, such as dodecyl dimethyl benzyl ammonium chloride (DDBAC), ZnO and graphene oxide (GO) nanosheets, onto the CNC's surface. Then, the DDBAC/CNC, ZnO/CNC and GO/CNC nanocomposites modified polyvinylidene fluoride (PVDF) ultrafiltration membranes were fabricated by a simple one-step non-solvent induced phase separation (NIPS) process. The resultant hybrid membranes possessed porous and rough surfaces with more finger-like macropores that even extended through the entire cross-section. The hydrophilicity, permeability, antibacterial and antifouling performance and mechanism of the hybrid ultrafiltration membranes were evaluated and compared in detail, aiming at screening a superior hybrid membrane for practical application in micro-polluted source water purification. Among these newly-developed hybrid membranes, GO/ CNC/PVDF exhibited an enhanced perm-selectivity with a water flux of 230 L/(m² h bar) and humic acid rejection of 92%, the improved antibacterial activity (bacteriostasis rate of 93%) and antifouling performance (flux recovery rate (FRR) of >90%) being due to the optimized pore structure, higher surface roughness, incremental hydrophilicity and electronegativity. A lower biofouling level after three weeks' filtration of the actual micro-polluted source water further demonstrated that embedding the hydrophilic and antibacterial GO/CNC nanocomposite into the polymer matrix is an effective strategy to improve membrane anti-biofouling ability. [ABSTRACT FROM AUTHOR]

Benzyl chloride and its derivatives are efficiently deprotonated with strong bases to form α‐chlorocarbanions. These anions are long‐lived enough to enter VNS reactions with nitroarenes or nitroheteroarenes to give a variety of unsymmetrical o‐ and p‐nitrodiarylmethanes. Selectivity of the reaction can be controlled to some extent by changing metal counterions of the base. [ABSTRACT FROM AUTHOR]

Abstract Electron capture detectors (ECDs) and detectors used in ion mobility spectrometry (IMS) have been successfully used for the detection of numerous compounds including hazardous substances. The general principles of their operations are similar and based on sample component ionization and measurement of the signal using the differences in the mobility of electric charge carriers. Differences in sensitivity result from various parameters of these instruments. Value of electric field intensity in ionic reactors have an influence on ionization process. The main goal of the performed tests was to compare the analytical properties of ECD and two types of IMS detectors: a drift tube spectrometer (DT IMS) and a differential mobility spectrometer (DMS). In the work performed, the efficiency of ionization and the response of detectors to selected analytes were compared. ECD, DT IMS and DMS were equipped with 63-Ni radioactive sources. Analytes have been ionized via electron capture process or dissociative electron transfer. Results obtained for oxygen and chloro-substituted organic compounds (carbon tetrachloride, benzyl chloride, chloroform, 2-chloroethyl ethyl sulfide) were used to calculate the relative signal and to compare the ionization efficiency for three detectors. The phenomena observed experimentally were related to energy dependencies and electron capture cross-sections of analytes. The efficiency of ionization in DT IMS was also compared for electron capture when nitrogen was used as the carrier gas, and when the ionization process was based on the collisions of the analyte molecules with the O 2 - with the use of air. Graphical abstract fx1 Highlights • Electron capture is effective method of ionization in ion mobility spectrometry. • Different types of detectors are compared. • Limits of detection of below 1 ppb level are achieved. • Electron energy is the factor determining ionization efficiency. • In some cases dissociative charge transfer is the effective way for ionization. [ABSTRACT FROM AUTHOR]

The organobase-mediated diastereoselective spirocyclopropanation of barbiturate-based olefins with 2,4-disubstituted benzyl chlorides has been developed. The reactions were carried out efficiently to afford the desired spirobarbiturate-cyclopropanes in up to 95% yield with more than 20:1 dr in favor of anti-isomers. In order to extend synthetic utility of the spiro-products, a Lewis acid induced cyclopropanering- expansion isomerization was also demonstrated. [ABSTRACT FROM AUTHOR]

The reactions of 3-benzyl-1,5-ditosyl-1,3,5-triazapentane (1) and 3-benzyl-1,5-dimesityl- 1,3,5-triazapentane (2) with one equivalent of Lappert´s germylene or stannylene (M[N(SiMe3)2]2, where M = Ge, Sn) produced germylenes and stannylenes of the general formula PhCH2N(CH2CH2NR)2M, where M = Ge, R = 4-MeC6H4SO2– (3); 2,4,6-Me3C6H2– (5); M = Sn, R = 4-MeC6H4SO2– (4); 2,4,6-Me3C6H2– (6), in satisfactory yields. According to NMR data (1H, 13C, 119Sn), stannylenes 4 and 6 are monomeric in solution, and the coordination number of tin is four. The synthesized stannylenes exhibited very high (compound 4) and moderate (compound 6) activity as initiators for bulk polymerization of ε-caprolactone, resulting in the synthesis of high-molecular-weight polymers with relatively narrow molecular-weight distribution. Previously unknown triamine 2 was synthesized by benzylation of HN(CH2CH2NHMes)2 with benzyl chloride in the presence of K2CO3. [ABSTRACT FROM AUTHOR]

A simple, facile, and convenient practical method for the one-pot synthesis of pharmaceutically interesting 5,5'-(1,4-phenylenebis-(methanylylidene))bis-thiohydantoins via a three-component condensation reaction of terephthalaldehyde, α-amino acids and isothiocyanates had been developed. The S-alkylated derivatives 6a and 6b were obtained by the alkylation of the bis-thiohydantoins 4a with methyl iodide and/or benzyl chloride in a basic media. The molecular structures of the synthesized compounds were confirmed by their elemental analyses and spectral data (IR, 1H, 13C NMR and MS). The assignment of more stable Z- or E-isomers as the major form of 4a, 6a, and 8a was investigated by DFT calculations at B3LYP/6-31+G* level. Some of the prepared compounds were screened for their in-vitro antimicrobial activity. Compounds 4a, 6 b, 8 b and 8c exhibited low antibacterial activity against gram-positive bacteria Bacillus cereus. (5Z,5′Z)-5,5′-(1,4-Phenylenebis(methanylylidene))bis(3-benzyl-2-thioxoimidazolidin-4-one) (4b) exhibited good fungicidal activity against Fusarium oxysporum. [ABSTRACT FROM AUTHOR]

Compounds containing 1,3,4-thiadiazole nucleus appear to be potential tyrosine kinase inhibitors. Previous reports showed that some 1,3,4-thiadiazole derivatives were designed as probable tyrosine kinase inhibitors. Thiol derivative (2) was obtained from the reaction of 5-amino-1,3,4-thiadiazole-2-thiol with 4-fluorophenylacetic acid, ethyldimethyaminopropylcarbodiimide and hydroxybenzotriazole. Subsequent reaction of the obtained thiol derivative with diverse benzyl chlorides afforded the final compounds 3a-3l in a click reaction surprisingly. Derivatives with electron withdrawing moieties (F, Cl) exerted higher yield compared to methoxylated derivatives as electron donating group. Besides, docking studies using ArgusLab 4.0 was done for exploring the probable binding mode and interactions. Investigation of cytotoxicity of target compounds (3a-3l) by MTT assay revealed that these derivatives are more active against the breast cancer cell line MCF-7 and most of these were found to be more effective than imatinib as reference drug. Chlorine containing derivatives at ortho and meta positions were the most cytotoxic in these series. [ABSTRACT FROM AUTHOR]

A straightforward, mild and efficient protocol for the synthesis of benzyl dithiocarbamates from benzyl chlorides and tetraalkylthiuram disulfides is presented. This protocol is compatible with a wide variety of electron‐donating and ‐withdrawing substituents and enables construction of various dithiocarbamate derivatives from readily available starting materials. A mild and efficient synthesis of benzyl dithiocarbamates through transition metal free cross‐coupling reactions was developed. This attractive methodology for the synthesis of benzyl dithiocarbamate derivatives is of great significance due to the potential utilization of the product in pharmaceutical industry. [ABSTRACT FROM AUTHOR]

The alkylation of cyanothioacetamide with benzyl chloride in DMF in the presence of 10% aqueous potassium hydroxide afforded 2,3-bis[amino(benzylsulfanyl)methylidene]butanedinitrile. Analogous reaction with addition of acetylacetone or its 3-methyl derivative led to the formation of 2-benzylsulfanyl-4,6-dimethylor -4,5,6-trimethylpyridine-3-carbonitrile. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Controllable palladium-catalyzed carbonylative transformation of benzyl chlorides. • Substituted phenylacetic acids and benzyl phenylacetates can be obtained from the same substrates. • In-situ generated benzylic formats can be used as the source of CO. Abstract With the strategy of in-situ generation of benzyl formates followed by alkoxycarbonylation, a palladium catalyzed carbonylative transformation of benzyl chlorides for the synthesis of benzyl arylacetates and arylacetic acids have been developed. By employing different acidic and basic additives, both substituted phenylacetic acids and benzyl phenylacetates can be obtained divergently. [ABSTRACT FROM AUTHOR]

Supported Co 3 O 4 nanoparticles on SBA-15 aluminosilicates (Al-SBA-15) with different cobalt loadings (0.5, 1, 5, 10 wt %) were synthesized by ball-milling. The synthesized materials were characterized by different techniques including, N 2 adsorption measurements, XRD, TEM, EDX, ICP-MS, DRIFTs of pyridine among others. The catalysts were studied in the microwave assisted benzyl alcohol oxidation as well as in the akylation of toluene with benzyl chloride. Co 3 O 4 catalysts exhibited moderate conversions in the selective oxidation of benzyl alcohol, with a high selectivity towards benzaldehyde. Lewis acidity increases upon the incorporation of cobalt nanoparticles onto the surface of the support which was found to significantly influence the materials in the alkylation of toluene with benzyl chloride. The high active sites accessibility of ball-milling prepared materials leads to high conversions to alkylated derivatives in short periods of time (>99 mol %, 30 min). A direct correlation acidity/activity could not be obtained in the systems, for which nanoparticle sizes and distribution could influence the observed activities. [ABSTRACT FROM AUTHOR]

Thermostable and fluorescent poly(phenylene methylene) (PPM) was synthesized via α‐Fe2O3/attapulgite (α‐Fe2O3/A)‐mediated polymerization of benzyl chloride (BC) in CCl4 in good yields. A carbocationic mechanism was proposed based on the controlling experiment. The structure and properties of PPM were characterized by Fourier transform infrared spectrometry, 1H and 13C nuclear magnetic resonance spectrometry, thermogravimetric analysis, elemental analysis, gel permeation chromatography, and UV–vis and fluorescence spectrometry. The results show that PPM possesses outstanding homoconjugation fluorescence and excellent thermal stability with onset decomposition temperature of ca. 420 °C. Recycled α‐Fe2O3/A proved to be still highly active for BC polymerization. Moreover, the strategy features low‐cost and readily accessible starting materials, simple one‐pot operation, and recyclable catalyst, facilitating future applications. © 2018 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2018, 56, 2280–2285 Thermostable and fluorescent poly(phenylene methylene) (PPM) was synthesized via α‐Fe2O3/attapulgite (α‐Fe2O3/A)‐mediated polymerization of benzyl chloride (BC) in CCl4 in good yields. The structure and property characterizations show that PPM possesses outstanding homoconjugation fluorescence and excellent thermal stability with an onset decomposition temperature of ca. 420 °C. Recycled α‐Fe2O3/A proved to remain highly active for BC polymerization. Moreover, the strategy features low‐cost and readily accessible starting materials, simple one‐pot operation, and a recyclable catalyst, facilitating future applications. [ABSTRACT FROM AUTHOR]

A convenient and highly efficient Pd-catalysed carbonylative annulation of salicylaldehydes with benzyl chlorides to afford the corresponding 3-arylcoumarins in good to excellent yields has been developed. Importantly, the protocol utilizes a commercially available, low cost, solid and easy to handle N-formylsaccharin as an alternative to the highly toxic CO gas. [ABSTRACT FROM AUTHOR]

Hazardous chemicals released from the petroleum-derived face mask can be inhaled by wearers and cause adverse health effects. Here, we first used headspace solid-phase microextraction coupled with GC-MS to comprehensively analyze the volatile organic compounds (VOCs) released from 26 types of face masks. The results showed that total concentrations and peak numbers ranged from 3.28 to 197 μg/mask and 81 to 162, respectively, for different types of mask. Also, light exposure could affect the chemical composition of VOCs, particularly increasing the concentrations of aldehydes, ketones, organic acids and esters. Of these detected VOCs, 142 substances were matched to a reported database of chemicals associated with plastic packaging; 30 substances were identified by the International Agency for Research on Cancer (IARC) as potential carcinogenic to humans; 6 substances were classified in the European Union as persistent, bioaccumulative, and toxic, or very persistent, very bioaccumulative substance. Reactive carbonyls were ubiquitous in masks, especially after exposure to light. The potential risk of VOCs released from the face masks were then accessed by assuming the extreme scenario that all the VOC residues were released into the breathing air within 3 h. The result showed that the average total concentration of VOCs (17 μg/m3) was below the criterion for hygienic air, but seven substances, 2-ethylhexan-1-ol, benzene, isophorone, heptanal, naphthalene, benzyl chloride, and 1,2-dichloropropane exceeded the non-cancer health guidelines for lifetime exposure. This finding suggested that specific regulations should be adopted to improve the chemical safety of face masks. [Display omitted] • Large amount of VOCs were detected from the face masks. • Light irradiation significantly affected the VOC release profile. • Hazardous VOCs released from the face masks were screened. • Seven compounds released from face masks were recognized as high-risk. [ABSTRACT FROM AUTHOR]

[Display omitted] • The conversion of carbohydrates to monosaccharides is 87.0%. • Adding water to DES promotes the conversion of carbohydrate to monosaccharides. • Xylose yield from hydrated DES hydrolyzate is higher than that of DES. • Glucose yield from enzymatic hydrolysis increases by 10.3 times. In this work, a rapid one-pot hydrated deep eutectic solvent (DES) pretreatment was proposed to facilitate the conversion of carbohydrates from lignocellulosic biomass to monosaccharides. Specifically, the pure and hydrated DES based on benzyl triethylammonium chloride (BTEAC), formic acid (FA) and water was used to pretreat bamboo shoot shells (BSS) by microwave heating. The pretreated solid residues were enzymatically saccharified to produce fermentable sugars, and the hydrolyzed carbohydrates and lignin remained in the hydrolyzate. The results showed that the yield of monosaccharides from the hydrated DES hydrolyzate (193.7–228.4 g/kg) was significantly higher than that (45.9–66.1 g/kg) of pure DES. The 30% hydrated DES pretreatment achieved the best glucose yield (89.03%) and a total monosaccharides yield of 555.4 g/kg, which corresponded to a conversion ratio of carbohydrates to monosaccharides of 87.0%. The proposed process is a robust method for the efficiently convert carbohydrates from BSS into monosaccharides. [ABSTRACT FROM AUTHOR]

4-(Benzyloxy)benzyl chloride polymer-bound (BBC-Polym) was functionalized with 1-phenyl-1 H -tetrazole-5-thiol (PTT), and the corresponding novel nano-particle Pd catalyst prepared by the subsequent addition of PdCl 2 (BBC-Polym@PTT@Pd). The Pd catalyst was characterized using powder XRD, SEM, EDX, ICP, TGA-DTA, and FT-IR spectroscopy. Then, the Pd catalyst was used as an efficient heterogeneous catalyst for the synthesis of various N -benzylated arylcyanamides at 60 °C in acetonitrile. [ABSTRACT FROM AUTHOR]

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Abstract: A metal and additive free process for the synthesis of benzyl chloride and α‐chloro alkyl arenes is reported. The proposed methodology can be carried out by the use of sunlight. The yield and conversion of the obtained benzyl chlorides are very high. [ABSTRACT FROM AUTHOR]

A novel strategy for a heterogeneous benzylation reaction conducted in a capillary microreactor was proposed. Silica-immobilized FeCl 3 nanocatalysts were dispersed in benzyl chloride to form a nanofluid, and then were applied for the benzylation of toluene with benzyl chloride to produce monobenzyl toluene and dibenzyl toluene. The effects of various factors, such as reaction temperature, catalyst composition and residence time on the reaction performance were systematically evaluated. The benzyl chloride conversion could reach 99.2% with the 10%FeCl 3 -SiO 2 catalyst under optimal conditions. Both internal effectiveness factor and external effectiveness factor were estimated to explore the influence of internal diffusion and external diffusion on the reaction performance and to reveal the rate-controlling step during the continuous-flow synthesis. Furthermore, the carbenium ions mechanism was applied to elaborate this heterogeneous benzylation reaction. The nanocatalysts could be regenerated and reused for three times with a high catalytic activity (conversion of benzyl chloride >70%), showing great application potential of this nanofluid catalysis protocol on chemical transformations for fine chemicals syntheses. [ABSTRACT FROM AUTHOR]

A Stille cross-coupling reaction was developed that delivers for the first time trifluoromethyl-substituted homoallyl compounds from α-(trifluoromethyl)benzyl chlorides and allylstannanes. This reaction proceeds even with low catalyst loadings (1 mol%) via a rare CF3–Pd–π-benzyl intermediate. [ABSTRACT FROM AUTHOR]

A novel synthetic route is reported for the preparation of anion exchange membrane and its application towards desalination via electrodialysis and acid recovery via diffusion dialysis. In current study a copolymer based on triethoxyvinylsilane and quaternized vinyl benzyl chloride was synthesized by free radical polymerization using AIBN as an initiator. Further, the property of copolymer was improved by adding different concentration of functionalized graphene nano-ribbons ( f GNR). Structural, chemical and morphological parameters was confirmed by FT-IR, AFM, SEM and TEM analysis. Prepared membrane shows excellent thermal, mechanical and chemical stability by the addition of f GNR. The performance of copolymer was analyzed in terms of electrochemical and physicochemical system. The PGR-5 membrane shows hydroxyl ion conductivity of 1.60 × 10 −2 S/cm, which is found to be double at 90 °C. The IEC of the membranes was also improved by addition of f GNR. In summary increasing the amount of f GNR in membrane matrix, IEC, ionic conductivity, hydration number, elastic modulus, thermal stability etc. increases while swelling ratio reduces by 30% for PGR-5 membrane compared to PVSi. Prepared composite membranes shows lower power consumption 1.36 kWh/kg with high current efficiency 88.68% for salt removal by electrodialysis. For recovery of HCl, PGR-5 membrane shows its superiority with dialysis coefficient of 0.053 m/h and separation factor of 41. Results show that PGR-5 membrane is a good candidate for electro-membrane processes and diffusion dialysis. [ABSTRACT FROM AUTHOR]

Traditionally benzylation of phenol is carried out with benzyl chloride which is corrosive and difficult to handle, and the resultant reaction is not atom economical. Benzyl alcohol is an alternative to benzyl chloride which is safe and easy to handle. Benzyl phenols are industrially important products particularly in plastic, rubber and petroleum industries. In present study, cesium salt of dodecatungstophosphoric acid (Cs 2.5 H 0.5 PW 12 O 40 , Cs-DTP) supported on mesocellular foam (MCF) silica was used as catalyst among others. The activity of prepared catalyst, 20% (w/w) Cs-DTP/MCF was compared with Amberlyst-15, montmorillonite clay K10, S-ZrO 2 and unsupported Cs-DTP catalyst. The supported catalyst showed better performance because of even distribution of acidic sites on MCF. The effect of reaction parameters were studied in detail and it was found that reaction follows second order kinetics. The activation energy was found to be 15.94 kcal/mol. The catalyst was found reusable. [ABSTRACT FROM AUTHOR]

Abstract: A novel catalytic feature of a hexameric resorcinarene capsule is highlighted. The self‐assembled cage was exploited to promote the Friedel–Crafts benzylation of several arenes and heteroarenes with benzyl chloride under mild conditions. Calculations showed that there are catalytically relevant hydrogen‐bonding interactions between the bridging water molecules of the capsule and benzyl chloride, which is fundamental for the activation of the C−Cl bond. The capsule controls the reaction outcome. Inside the inner cavity of the capsule, N‐methylpyrrole is preferentially benzylated in the unusual β‐position while mesitylene reacts faster than 1,3‐dimethoxybenzene despite the greater π‐nucleophilicity of the latter compound. [ABSTRACT FROM AUTHOR]

Several novel 2-naphthol-pyrazole conjugates have been synthesized through the O-alkylation of 1-[(3,5-dimethyl-1H-pyrazol-1-yl)methyl]naphthalen-2-ol with methyl iodide, benzyl chloride, methyl bromoacetate and N-benzyl-2-bromoacetamide. The aminomethylation of these 2-naphthol-pyrazole conjugates has been examined employing the classical conditions for the Mannich reaction, and also by using N,N-dimethylmethyleneiminium chloride as preformed aminomethylating reagent. In both situations, aminomethylation of these substrates occurred at C-4 of the pyrazole ring. The bifunctional substrate 1-[(3,5-dimethyl-1H-pyrazol-1-yl)methyl]naphthalen-2-ol has been chemoselectively aminomethylated in the pyrazole ring using the same preformed aminomethylating reagent. [ABSTRACT FROM AUTHOR]

Abstract: This work reported a novel immobilization method of penicillin acylase (PA) using nucleophilic substitution reaction between benzyl chloride on macroporous adsorption resin (MAR) and amino groups on PA. Nucleophilic substitution reaction of benzyl chloride was reported for the first time in enzyme immobilization. The work was conducted as follows: Firstly, an apolar MAR, LX1180, was chemically modified, that is, chloromethylated, to prepare benzyl chloride LX1180 (CLX1180). Then, CLX1180 was used as a support to immobilize PA through nucleophilic substitution. The influence of reaction conditions, such as immobilization time, temperature, pH, and the amount of PA, on the loading ratio and catalytic activity were investigated and optimized. Besides, this study indicated that the immobilization reaction was a diffusion‐controlled reaction. Finally, the structure of immobilized PA was characterized using FTIR, and the stability for catalyst activity was explored by investigating the reusability of the sample, and the result indicated that PA was immobilized on the surface of CLX1180 successfully and presented an excellent stability of catalyst activity. It proposed a simple and promising way to immobilize PA for enzyme catalysis. [ABSTRACT FROM AUTHOR]

We report on the synthesis and characterization of amphiphile copolymers derived from poly( N , N -dimethylaminoethyl methacrylate) (PDMAEMA) generated by the stepwise quaternization of PDMAEMA, first with 1-hexadecyl bromide (HDB) and then with benzyl chloride (BC). Amphiphile copolymers consisting of hydrophile blocks separated by hydrophobe units were thus prepared in a predictable manner. The chemical structure of the hydrophobically modified polycations was confirmed by FTIR and 1 H NMR spectroscopy, and by elemental analysis. The behavior in salt-free aqueous solutions was investigated by viscometry at 25 °C, rheological investigations at different temperatures, and by SAXS measurements. The steady shear measurements revealed an aggregation during the flow at moderate shear rates, the amplitude of this phenomenon depending on the hydrophobic/hydrophilic balance. The clusters are formed due to the intermolecular interactions and they grow as the shear rate is approaching 1 s −1 . For the temperatures between 45 °C and 65 °C, the shear forces determine an expansion of the macromolecules that tend to orient in the flow direction and favor either a better interaction of the hydrophilic groups with the water molecules, or the manifestation of hydophobic interactions. The associative properties and the micelles geometry were tuned by the content and distribution of the hexadecyl groups. [ABSTRACT FROM AUTHOR]

Quaternary ammonium salts are widely used as epidermal and topical antimicrobial agents in medical treatments due to their broad activity, excellent performance and ready availability. However, their epidermal application has revealed many noticeable disadvantages, including short-term functionality, environmental toxicity, rapid antimicrobial resistance and skin penetration. Here, a series of tri-block copolymers grafted with dimethylaminopropyl benzyl chloride and based on a polydimethylsiloxane (PDMS) backbone, referred to as PDMS- b -(PDMS- g -BC)- g -PDMS, were prepared with well-controlled chain length and cationic grafting content. The quaternary ammonium salt-containing polymers were effective antimicrobial agents against epidermal pathogenic microbes, such as E. coli , S. albus and C. albicans . By incorporating hydrophilic and antimicrobial quaternary ammonium salt groups into the hydrophobic PDMS backbones, the amphiphilic tri-block copolymers were water-soluble but capable of assembling onto different surfaces, driven by electrostatic attraction or hydrophobic repulsion, which yielded long-term functionality on the surface. Moreover, the enlarged molecular size prevented penetration though full-thickness rat skins. These findings suggest a promising application of polymeric quaternary ammonium salts with hydrophobic moieties as epidermal antimicrobial agents. [ABSTRACT FROM AUTHOR]

Abstract: The results of our investigations on the preparation of 3a,8a‐dihydroxyindeno[1,2‐d]imidazole derivatives via reaction of thiourea, ninhydrin, and alkyl/benzyl chlorides in aqueous ethanol and under convenient conditions is reported. On the other hand, when guanidinium chloride was used instead of thiourea, the reaction mixtures reached with unexpected products; 2,2‐dialkoxy‐1H‐indene‐1,3(2H)‐diones. [ABSTRACT FROM AUTHOR]

ABSTRACT Poly(phenylene methylene) (PPM) was isolated in a broad range of molar masses by optimization of the catalytic polymerization of benzyl chloride with SnCl4 or FeCl3, followed by fractionation by Soxhlet extraction or phase separation in concentrated solutions in poor solvents. Low molar mass products were also obtained by quenching the reaction at moderate monomer conversions. Products with number average molar masses ( Mn) ranging from 200 to 61,000 g mol−1 were isolated, the latter being an order of magnitude above the previously reported values. DSC analysis of polymers of different molar masses revealed that the glass transition temperature follows the Flory-Fox equation reaching a plateau value of 65 °C at a molar mass between 10,000 and 20,000 g mol−1. The onset of decomposition temperature of higher molar mass products proceeds above 450 °C (maximum decomposition rate at 515 °C), according to TGA. Furthermore, the substitution pattern of PPM was discussed by study of chemical shifts of the methylene group [ABSTRACT FROM AUTHOR]

The Suzuki-Miyaura cross-coupling (SMC) reactions of several heteroaryl chlorides, benzyl chlorides, and aryl acid chlorides with (hetero)arylboron reagents have been investigated in the presence of [Pd(HL1)(PPh3)Cl2] ( I) [HL1 = 3-[(2,6-diisopropylphenyl)-1-imidazolio]-2-quinoxalinide] as catalyst and K2CO3 as base in neat water. The synthesis of the heterocycle-containing biaryls required the addition of 2 mol-% of a phosphine ligand (PPh3 or X-Phos). A combination of more than 115 substrates were screened and it was found that I is a versatile catalyst that can produce heterocycle-containing biaryls, diarylmethanes, and benzophenones in moderate-to-excellent yields. [ABSTRACT FROM AUTHOR]

We synthesized poly(poly(ethylene glycol)methyl ether methacrylate)- b -poly(2-(dimethylamino)ethyl methacrylate) (p(PEGMA- b -DMAEMA)) by sequential addition of monomers and its quaternized products (p(PEGMA- b -(DMAEMA- co -QDMAEMA)) from the reaction with benzyl chloride for dispersion of copper phthalocyanine (CuPc). The structure of block copolymers was characterized by 1 H NMR and GPC analysis. The block copolymers were investigated for their dispersion performance of CuPc in propylene glycol monomethyl ether acetate. The dispersion states of CuPc by dispersants were studied using dynamic light scattering. [ABSTRACT FROM AUTHOR]

A well-defined molecularly imprinted polymer nanospheres with excellent specific recognition ability was prepared on Fe 3 O 4 nanoparticles via the combination of click chemistry and surface-initiated reversible addition−fragmentation chain transfer (RAFT) polymerization and using Tetrabromobisphenol A as template. Concretely, Fe 3 O 4 nanoparticles were prepared by solvothermal method and then modified by 4-vinylbenylchloride through distillation-precipitation, which makes azide groups easily introduced on the surface of magnetic nanoparticles to form the relatively large amount of benzyl chloride groups. With high efficiency, alkyne terminated RAFT chain transfer agent were then immobilized onto the surface of Fe 3 O 4 by means of click chemistry, which is Cu(I)-catalyzed azide–alkyne cycloaddition (CuAAC). The highly uniform imprinted thin film was finally fabricated on the surface of RAFT agent modified Fe 3 O 4 nanoparticles. The binding results demonstrated that as-prepared imprinted beads exhibited remarkable molecular imprinting effects to the template molecule, fast rebinding kinetics and an excellent selectivity to compounds with similar configuration. [ABSTRACT FROM AUTHOR]

[Display omitted] • The first oral-administration near-infrared fluorescence molecular (NS-V) for detection the variation of viscosity was established. • The probe NS-V was developed on the basis of naphthalene and pyridine benzyl chloride salt, and emitted at NIR region (710 nm). • The robust probe NS-V possesses a large Stokes shift (∼262 nm in MeCN) and high signal-to-noise ratio. • The new probe NS-V can elucidate the variations of mitochondrial viscosity in abnormal state cells. • The robust probe NS-V was realized in situ visualization the changes of viscosity in gastritis mice, for the first time. Gastritis is one of the most common digestive disorders and affecting millions of people worldwide. Recent investigations discovered that abnormal viscosity changes in organisms are associated with an increasing number of diseases that cannot be cured or managed. However, the relationship between gastritis and viscosity has not been explored so far due to lacking the suitable tools for in situ detecting the variations of viscosity in stomach. Herein, we developed a new oral-administration fluorescent probe (NS-V) for in situ elucidation of gastritis viscosity variations, for the first time. Based on the TICT mechanism, the probe employs naphthalene as the fluorescence platform, the rotatable single bond as the viscosity sensitive site, N, N -dimethyl as the strong electron donating moiety and the pyridine salt as the strong withdrawing group to enlarge the π-conjugated system to prolong the emission wavelength. Interestingly, NS-V revealed a good fluorescence response for viscosity at the NIR region from a silent "off" state to "on" and demonstrated high sensitivity, large Stokes shift (262 nm in MeCN), and high signal-to-noise ratio. In addition, NS-V could elucidate the altered mitochondrial viscosity in inflammatory cells. More importantly, utilizing these satisfactory features of NS-V , we discovered a significant increase in viscosity in the gastritis mice. Notably, with the assistance of the oral fluorescence molecule, in vivo and in situ visualizing for the first time revealed the positive correlation between viscosity and gastritis. This work provides an important basis for the diagnosis of gastritis and the robust probe developed in this work possesses a potential application in diagnosis of gastritis without any pain. [ABSTRACT FROM AUTHOR]

The alkylation of toluene, reaction employing benzyl chloride as the alkylating agent over basic hydrotalcite materials: Fe–Mg–Al-LDH prepared by different synthesis methods, including the method of co-precipitation, impregnation and a new method called the method of intercalation by anion exchange in the lamellar space of the host structure LDH. Our prepared solids were characterized by chemical analysis, XRD analysis, BET method and thermogravimetric analysis (TGA) and tested in the alkylation of toluene by benzyl chloride reaction. Fe–Mg–Al-LDH clay without or with calcination (at 773 K) has been investigated. The catalyst derived from the hydrotalcite by its calcination at 773 K shows high catalytic activity for the alkylation of toluene and other aromatic compounds. The catalytically active species present in the catalyst in its most active form are the oxides of iron on the catalyst surface.

The benzylation of benzene by benzyl chloride over a series of Thallium-containing mesoporous silicas with different Tl contents has been investigated. These materials (Tl-HMS-n) have been characterized by chemical analysis, N2 adsorption/desorption isotherm and X-ray diffraction (XRD). The mesoporous Thallium-containing materials showed both high activity and high selectivity for the benzylation of benzene. More interesting is the observation that these catalysts are always active and selective for large molecules like naphthenic compounds such as methoxynaphthalene.