Benzyl Chloride Research Articles

Preparation and alkaline stability of polyethylene composite hydroxide exchange membranes with different cations

Hydroxide exchange membrane fuel cells (HEMFCs) are a cost-effective alternative to proton exchange membrane fuel cells due to the advantages on fast oxygen reduction reaction kinetics, low cost and weak corrosion. Hydroxide exchange membrane (HEM) is the core component for HEMFC. At present, lacking highly robust and chemically stable HEMs is the main challenge to realizing durable HEMFCs. Polyethylene composite HEMs are considered as the-state-of-the-art HEM candidates due to their excellent mechanical properties, thus allowing for the use of ultrathin HEMs in HEMFCs to achieve a high cell and stack performance. Yet, the chemical stability of polyethylene composite HEM still needs to be improved for more durable HEMFC. In this study, we report that the preparation and chemical stability understanding of three polyethylene composite HEMs (named AEH-TMA, AEH-DMP and AEH-TMI) functionalized with trimethylamine (TMA), N-methylpiperidine (DMP) and 1, 2, 4, 5-tetramethylimidazole (TMI), respectively. We find that AEH-TMI exhibits a low conductivity and inferior chemical stability in comparison to AEH-TMA and AEH-DMP. To gain insight into chemical stability behavior, we have also prepared three organic chemicals (named Bn-TMA, Bn-DMP and Bn-TMI) as cations model by reacting benzyl chloride with TMA, DMP and TMI cations and elaborately studied their chemical stability in various water content systems. The results show that the overall chemical stability of cations can be strongly improved with increasing the surrounding water, and Bn-TMI suggests a lower chemical stability than Bn-TMA and Bn-DMP at high water content condition.

A Facile Synthesis and Molecular Characterization of Certain New Anti-Proliferative Indole-Based Chemical Entities.

Cancer cells frequently develop drug resistance, which leads to chemotherapeutic treatment failure. Additionally, chemotherapies are hindered by their high toxicity. Therefore, the development of new chemotherapeutic drugs with improved clinical outcomes and low toxicity is a major priority. Several indole derivatives exhibit distinctive anti-cancer mechanisms which have been associated with various molecular targets. In this study, target compounds 4a-q were obtained through the reaction of substituted benzyl chloride with hydrazine hydrate, which produces benzyl hydrazine. Subsequently, the appropriate substituted benzyl hydrazine was allowed to react with 1H-indole-2-carboxylic acid or 5-methoxy-1H-indole-2-carboxylic acid using 1-ethyl-3-(3-dimethylaminopropyl)carbodiimide as a coupling agent. All compounds exhibited cytotoxicity in three cell lines, namely, MCF-7, A549, and HCT. Compound 4e exhibited the highest cytotoxicity, with an average IC50 of 2 µM. Moreover, a flow cytometry study revealed a significantly increased prevalence of Annexin-V and 7-AAD positive cell populations. Several derivatives of 4a-q showed moderate to high cytotoxicity against the tested cell lines, with compound 4e having the highest cytotoxicity, indicating that it may possess potential apoptosis-inducing capabilities.

Evaluation of Physicochemical and Amphiphilic Properties of New Xanthan Gum Hydrophobically Functionalized Derivatives

This research aimed to develop new hydrophobic and potentially amphiphilic benzyl xanthan gum (BXG) derivatives using a Williamson synthesis. This modification consists of an etherification reaction between xanthan gum (XG) and benzyl chloride (BC) under microwave heating. The effects of the molar ratio (R = XG/CLB, with R equal to 2 or 4) on the amphiphilic character and the degree of substitution (DS) were studied. The two benzyl xanthan gum derivatives (BXG1 and BXG2) were subsequently subjected to various physicochemical and rheological characterization techniques. The obtained results of FTIR and H1-NMR spectroscopy showed the effectiveness of the grafting of aromatic moieties onto the XG molecule with DS values of 0.59 for BXG1 and 0.7 for BXG2. The XRD analysis revealed slight modifications in the xanthan crystallinity after etherification, where the degree of crystallinity (DOC) values were 8.46%, 10.18%, and 14.67% for XG, BXG1, and BXG2, respectively. Additionally, conductivity measurements showed that the BXG derivatives exhibit higher values than native XG, due to the inter- and intra-molecular associations following the grafting of aromatic groups. Moreover, the critical aggregation concentration (CAC) was detected at 0.32% for BXG1 and 0.28% for BXG2. The rheological study confirmed that XG and its BXG derivatives exhibited a shear-thinning pseudoplastic behavior and that the viscosity increases when the DS increases. The emulsifying power test of the BXGs compared to the native XG confirmed the amphiphilic properties of the new benzylated derivatives, where the stabilizing capacity increases with increased DS.

Evaluating the Sapindusrarak DC Chemical compounds for their ability to inhibit the growth of Fusobacterium nucleatum In vitro

The development of natural resources in the root canal irrigant in endodontic treatment has increased to answer biocompatibility issues. The Lerak (Sapindusrarak DC) fruit, known in Indonesia as a traditional soap seed, can be used as an alternative irrigant for root canal irrigation. It almost qualifies as an irritant. This study aimed to determine the antibacterial compound of Sapindusrarak DC (S. rarak DC). That Predicts as the alternative to root canal irrigation. Gas Chromatography-Mass Spectrometry (CG - MS) was used to identify the compounds of Sapindusrarak DC. The results of GC/MS analysis show that the Sapindusrarak DC has bioactive components such as benzyl chloride, 1-Dodecanamine, N, N-Dimethyl-, 1-Tetradecanamine,N,N- Dimethyl, 4- (3-Dimethylaminopropoxy) benzaldehyde, 1- (Dimethylamino) –2- Butanol, Acetamide, 2-(Diethylamino)-N- (2,6-Dimethylphenyl, 9-Octadecenoic Acid, Hexadecanoic Acid, Cis- 13-Octadecenoic acid, methyl ester, Tetrahydroquinoline-4,4,-, 6-Octadecenoic acid, 2- (BenzylmethylamiNomethyl) -2-Norbornone, Cis-13-Eicosenoic acid. At the 24-hour incubation period in a 12.5 percent Sapindusrarak DC, only 0.4% of F. nucleatum survived ina 100 percent salivary growth response. While a saliva concentration of 25% resulted in a growth response of 82 percent, F. nucleatum growth was only 18%. The concentration of 6.25% was then added, followed by CHX. At 48 hours, the S.rarak DC of 12.5% and 6.25% had a better growth response to F. nucleatum than other concentrations. However, CHX was still higher, giving a growth response to F. nucleatum (98.42%). This finding indicates that Sapindusrarak DC has the compound antibacterial to prevent F. nucleatumgrowth, of could be a recommendation as an alternative to natural root canal irrigation in the field of endodontic treatment.

Experimental Analysis and Neural Network Modeling of the Rheological Behavior of Xanthan Gum and Its Derivatives

The main objective of this study was to create a mathematical tool that could be used with experimental data to predict the rheological flow behavior of functionalized xanthan gum according to the types of chemical groups grafted onto its backbone. Different rheological and physicochemical analyses were applied to assess six derivatives synthesized via the etherification of xanthan gum by hydrophobic benzylation with benzyl chloride and carboxymethylation with monochloroacetic acid at three (regent/polymer) ratios R equal to 2.4 and 6. Results from the FTIR study verified that xanthan gum had been modified. The degree of substitution (DS) values varying between 0.2 and 2.9 for carboxymethylxanthan gum derivatives were found to be higher than that of hydrophobically modified benzyl xanthan gum for which the DS ranged from 0.5 to 1. The molecular weights of all the derivatives were found to be less than that of xanthan gum for the two types of derivatives, decreasing further as the degree of substitution (DS) increased. However, the benzyl xanthan gum derivatives presented higher molecular weights varying between 1,373,146 (g/mol) and 1,262,227 (g/mol) than carboxymethylxanthan gum derivatives (1,326,722-1,015,544) (g/mol). A shear-thinning behavior was observed in the derivatives, and the derivatives' viscosity was found to decrease with increasing DS. The second objective of this research was to create an ANN model to predict one of the rheological properties (the apparent viscosity). The significance of the ANN model (R2 = 0.99998 and MSE = 5.95 × 10-3) was validated by comparing experimental results with the predicted ones. The results showed that the model was an efficient tool for predicting rheological flow behavior.

Titanium-Catalyzed Hydrodehalogenation of Alkyl Halides

Hydrodehalogenation is a straightforward approach to detoxifying harmful organohalides, in which the halogen atom is formally substituted with a hydrogen atom. Herein, a catalytic system using Cp2TiCl2 as the catalyst and ammonia–borane as the reductant is described. A series of benzyl halides and inactivated alkyl halides (including alkyl chlorides) readily reacted to give the corresponding hydrodehalogenated products in yields of up to 97% (43 examples).

Deuterodehalogenation Under Net Reductive or Redox‐Neutral Conditions Enabled by Paired Electrolysis

AbstractInterest in deuterated active pharmaceutical ingredients (APIs) is increasing as deuteration holds promise for kinetic isotope effect (KIE) regulated fine‐tuning of API performance. Moreover, deuterium isotope labeling is frequently carried out to study organic and bioorganic reaction mechanisms and to facilitate complex target synthesis. As such, methods for highly selective deuteration of organic molecules are highly desirable. Herein, we present an electrochemical method for the selective deuterodehalogenation of benzylic halides via a radical‐polar crossover mechanism, using inexpensive deuterium oxide (D2O) as the deuterium source. We demonstrate broad functional group compatibility across a range of aryl and heteroaryl benzylic halides. Furthermore, we uncover a sequential paired electrolysis regime, which permits switching between net reductive and overall redox‐neutral reactions of sulfur‐containing substrates simply by changing the identity of the sacrificial reductant employed.

Deuterodehalogenation Under Net Reductive or Redox-Neutral Conditions Enabled by Paired Electrolysis.

Interest in deuterated active pharmaceutical ingredients (APIs) is increasing as deuteration holds promise for kinetic isotope effect (KIE) regulated fine-tuning of API performance. Moreover, deuterium isotope labeling is frequently carried out to study organic and bioorganic reaction mechanisms and to facilitate complex target synthesis. As such, methods for highly selective deuteration of organic molecules are highly desirable. Herein, we present an electrochemical method for the selective deuterodehalogenation of benzylic halides via a radical-polar crossover mechanism, using inexpensive deuterium oxide (D2 O) as the deuterium source. We demonstrate broad functional group compatibility across a range of aryl and heteroaryl benzylic halides. Furthermore, we uncover a sequential paired electrolysis regime, which permits switching between net reductive and overall redox-neutral reactions of sulfur-containing substrates simply by changing the identity of the sacrificial reductant employed.

Transition-Metal-Free Synthesis of Polyfluoro-Polyarylmethanes via Direct Cross-Coupling of Polyfluoroarenes and Benzyl Chlorides.

The transition-metal-free direct cross-coupling between polyfluoroarenes and benzyl chlorides is reported. In this strategy, a variety of polyfluoro di-, tri- and tetra-arylmethanes was efficiently prepared with good to excellent yields in the presence of Mg turnings via a one-pot procedure. Significantly, this method provides a general approach for the synthesis of polyfluorinated polyarylmethanes.

Synthesis of Novel DPPH-Free Radical Scavenger Se-Containing Fused Chalcogenophenes: 2-Alkyl-7-Cyano-4-Imino-3-Phenyl-6-(pyrrolidin-1-yl)-3,4-Dihydroselenopheno[3,2-d]Pyrimidines

A straightforward and effective strategy for the synthesis of novel 7-cyano-4-imino-3-phenyl-6-(pyrrolidin-1-yl)-2-substituted-3,4-dihydroselenopheno[3,2-d]pyrimidines have been accomplished through a base-promoted cascade addition/cyclization sequence employing phenyl isothiocyanate followed by the S-alkylation of the obtained fused Se-containing heterocyclic framework with various alkyl halides. Free radical scavenging activity of the synthesized selenium-containing structures was studied against DPPH, as well. Antioxidant activities as IC50 values were ranged from 12.19 to 91.08 µM. Unfused 3-amino-2,4-dicyano-5-(pyrrolidin-1-yl)selenophene was much more powerful antioxidant agent than ascorbic acid. Moreover, the promising antioxidant potentials were observed with selenopheno[3,2-d]pyrimidines. Taking into account the best antioxidant activity of S-benzylated derivative amongst pyrimidine-fused heterocycles and significant relationship between antioxidant activity of compounds and many of their biological potencies, using benzyl halides bearing electron donating groups on phenyl ring can probably improve their antioxidant capacities to make them more effective anti-cancer, anti-diabetic, anti-inflammatory and anti-neurodegenerative agents.

Cross-Linked, Monovalent Selective Anion Exchange Membrane: Effect of Prealkylation and Co-ions on Selectivity

Tuning of hydrophobicity, water uptake, and size of the ion channel is very crucial for the monovalent anion-selective membrane (MASM) preparation. In this work, we report the preparation of MASM from the cross-linked polyacrylonitrile-co-polyvinylimidazole (PAN-co-PVI) copolymer. The copolymer was in situ quaternized and cross-linked using the polyacrylonitrile-co-polychloromethylstyrene (PAN-co-PCMSt) copolymer as cross-linker. The benzyl chloride moiety (Ar-CH2Cl) of PAN-co-PCMSt reacts with imidazolium nitrogen of PAN-co-PVI and provides a positive charge on the membrane matrix, whereas the PAN moiety provides greater compatibility with the PAN-co-PVI copolymer matrix. The faster cross-linking without external prealkylation forms a strong network structure with a low ionic charge on the membrane surface. Judicious extent of prealkylation followed by cross-linking forms a controlled network structure and small-sized ionic channel with moderate water uptake and good mechanical stability. The representative AEM0Q and AEM17Q membranes with 0 and 17% prealkylation exhibited a permselectivity (PSO42–Cl–) value of 4.39 and 15.40, respectively, during the separation of 0.01 M NaCl + 0.01 M Na2SO4 by electrodialysis. Upon further increase of prealkylation to 27 and 32%, the water uptake of the membrane increased, which in turn allowed the passage of SO42– along with Cl– and decreased the PSO42–Cl–value to 4.12 and 2.45, respectively. Similar trends were observed during the separation of NaCl + MgSO4, MgCl2 + Na2SO4, and MgCl2 + MgSO4 mixtures of each 0.01 M concentration.

Polyvinyl alcohol-mediated electrospun nanofibers of synthetic 4-(benzyloxy)-3,5-dimethoxybenzaldehyde and β-Cyclodextrin and its biological applications

The compound4-(benzyloxy)-3,5-dimethoxybenzaldehyde (4BDBA), is primarily synthesized from syringaldehyde and benzyl chloride. These compounds have significant biological properties such as anti-oxidant, anti-microbial, and antifungal activity. The synthesized product is characterized using 1HNMR and FT-IR spectral analysis. In order to improve the solubility of 4BDBA, β-Cyclodextrin (β-CD) is added to 4BDBA in an aqueous medium and formed the inclusion complexes (ICs). Further, bio-composite materials in the form of nanofiber with 4BDBA:β-CD-ICs are obtained by using the electrospinning process with the help of polyvinyl alcohol (PVA). Nanofibers (NFs), in general, have various advantages like high surface-to-volume ratio, porosity, and mechanical and thermal stability. The surface morphology of 4BDBA:β-CD-ICs/PVA NFs, also revealed the uniform, bead-free NFs with 520.0–560.0 nm and exhibited the complete 4BDBA:β-CD-ICs dispersion in polymers at the nanoscale. The thermal stability and mechanical property of the material havealso been examined. The bacterial strains of Escherichia coli and Staphylococcus aureus showed antibacterial activity of the NFs using the disc-diffusing agar method. Overall findings indicate that these materials are useful in food packaging applications.

Chemical Burn From Benzyl Chloride With Secondary Eczematization.

Dermatitis®Ahead of Print LetterChemical Burn From Benzyl Chloride With Secondary EczematizationSophie Carrie Shan Cai, Zeenathnisa Mougammadou Aribou, Suzanne Wei Na Cheng, Anthony Teik Jin Goon, and Sylvia Tzu Li TeoSophie Carrie Shan CaiSophie Carrie Shan Cai (MD, MRCP (UK)), Dermatology Department, National Skin Centre, SingaporeSearch for more papers by this author, Zeenathnisa Mougammadou AribouZeenathnisa Mougammadou Aribou (BSc, MBBS, MPH (OM)), Preventive Medicine Department, National University Hospital System, SingaporeSearch for more papers by this author, Suzanne Wei Na ChengSuzanne Wei Na Cheng (MBBS, MRCP (UK)), Dermatology Department, National Skin Centre, SingaporeSearch for more papers by this author, Anthony Teik Jin GoonAnthony Teik Jin Goon (MBBS, MRCP (UK), FRCP (Edin), PhD), Dermatology Department, National Skin Centre, SingaporeSearch for more papers by this author, and Sylvia Tzu Li TeoSylvia Tzu Li Teo (MBBS, MMED (OM)), Occupational Safety and Health Specialist Department, Occupational Safety and Health Division, Ministry of Manpower, Singapore E-mail Address: sylvia_teo@mom.gov.sgSearch for more papers by this authorPublished Online:1 Feb 2023https://doi.org/10.1089/derm.2022.29018.sscAboutSectionsView articleView Full TextPDF/EPUB Permissions & CitationsDownload CitationsTrack CitationsAdd to favorites Back To Publication ShareShare onFacebookTwitterLinked InRedditEmail View article"Chemical Burn From Benzyl Chloride With Secondary Eczematization." Dermatitis, , pp. –FiguresReferencesRelatedDetails Volume 0Issue 0 Information© 2021 American Contact Dermatitis Society. All Rights Reserved.To cite this article:Sophie Carrie Shan Cai, Zeenathnisa Mougammadou Aribou, Suzanne Wei Na Cheng, Anthony Teik Jin Goon, and Sylvia Tzu Li Teo.Chemical Burn From Benzyl Chloride With Secondary Eczematization.Dermatitis®.ahead of printhttp://doi.org/10.1089/derm.2022.29018.sscOnline Ahead of Print:February 1, 2023PDF download

Bench-stable oxidant sodium percarbonate for functional group transformation of arylboronic acids

Sodium percarbonate (2Na2CO3·3H2O2, sodium carbonate-hydrogen peroxide, SPC), an easily accessible and bench-stable hydrogen peroxide-solid adduct based on inorganic salt, was efficiently used as a solid hydroxylating reagent for the ipso-hydroxylation of arylboronic acids under mild conditions, affording the corresponding phenols in an excellent manner at a fast rate. Moreover, a solvent-free solid-state reaction system using SPC for the oxidative hydroxylation of arylboronic acids was also demonstrated. Furthermore, subsequent treatment with benzyl halide was successfully performed, providing an alternative synthetic route for preparing benzyl phenyl ethers in a one-pot tandem reaction system.

Transition-metal-mediated benzylation of C60 with benzyl chlorides.

Benzyl bromides have been widely used for fullerene functionalization. However, the use of benzyl chlorides, a more affordable but less reactive counterpart of benzyl bromides, has been rarely reported. Herein, a new metal-mediated benzylation of C60 with benzyl chlorides is presented. In this method, with the combinatorial use of Mn powder and Cu(OAc)2, various benzyl chloride derivatives could react with C60 to afford 1,4-dibenzylated products in 12-53% yields. A mechanistic study by in situ visible near infrared (vis-NIR) spectroscopy and various control experiments suggests that, unlike the conventional anionic pathway that uses benzyl bromides, the transition-metal-mediated benzylation of C60 with benzyl chlorides proceeds via a metal-mediated iterative single electron transfer process.

One-pot synthesis of multisubstituted propenylbenzenes from benzyl chlorides through relay catalysis of palladium.

A strategy for the synthesis of multisubstituted propenylbenzenes using benzyl chlorides as starting materials is described. The palladium-catalyzed allylative dearomatization and the subsequent Wagner-Meerwein rearrangement as well as the olefin isomerization proceeded smoothly under mild conditions to produce propenylation products in good yields with high regioselectivity. Control experiments and cyclic voltammetry analysis suggest that Bu3SnCl, a by-product generated in the first step of allylative dearomatization, plays an essential role in the third step of olefin isomerization in the presence of a Brønsted acid.

Visible light-induced cascade N-alkylation/amidation reaction of quinazolin-4(3H)-ones and related N-heterocycles.

An efficient and visible light-promoted cascade N-alkylation/amidation of quinazolin-4(3H)-ones with benzyl halides and allyl halides has been described for the first time to provide a convenient access to quinazoline-2,4(1H,3H)-diones. This cascade N-alkylation/amidation reaction shows good functional group tolerance and could also be applied to N-heterocycles such as benzo[d]thiazoles, benzo[d]imidazoles, and quinazolines. Control experiments show that K2CO3 plays an important role in this transformation.

Insights into reactivity trends for electrochemical C-N bond formations.

Electrochemical synthesis techniques are currently of great interest due to the possibility of synthesizing products while limiting reactant and energy input and providing potentially unique selectivity. Our group has previously reported the development of the "anion pool" synthesis method. As this is a new method for organic synthesis and the coupling of C-N bonds, it is important to understand the reactivity trends and limitations this method provides. In this report we explore the reactivity trends of a series of nitrogen-containing heterocycles under reductive electrochemical conditions. The results show that anionic nitrogen heterocycles are stable at room temperature in acetonitrile/electrolyte solutions up to a parent N-H pKa value up to 23. Addition of carbon electrophiles to solutions containing the electrochemically generated anionic nitrogen heterocycles led to the C-N cross-coupling reactivity. Product yields tracked linearly with the pKa value of the N-H bond of the heterocycles over 4 orders of acidity magnitude. Both benzylic halides and perfluorinated aromatics were found suitable for undergoing C-N cross-coupling with the anionic nitrogen heterocycles with product yields as high as 90%. It is also shown that the stability and reactivity of the anions are affected by the choice of electrolyte and temperature. Additionally, this procedure compares well to green chemistry processes in atom economy and PMI values.

PREPARATION AND PROPERTIES OF CHLORINATED POLYISOBUTYLENE ELASTOMER BY ONE-STEP POLYMERIZATION

ABSTRACT Cationic copolymerization of isobutylene and chlorostyrene was investigated using the Lewis acid initiator system. Titanium (IV) chloride (TiCl4) and ethylaluminum sesquichloride (AlEt1.5Cl1.5) were used as the co-initiators, and 2-chloro-2,4,4-trimethylpentane (TMPCl) and H2O were used as the main initiators. The influences of monomer feeding ratio and reaction time were studied. The reaction mechanism was proposed by studying the reaction kinetics. It was found that when p-chloromethylstyrene (p-ClMSt) was used, benzyl chloride was easily involved in the initiation reaction stage, leading to the formation of branched polymer. When p-chlorostyrene (p-ClSt) was used as a co-monomer, living copolymerization was achieved and no branching structure formed. Isobutylene, isoprene, and p-ClSt were synthesized with the AlEt1.5Cl1.5 initiator system. The high-molecular-weight halogenated ternary copolymer was successfully prepared by one-step polymerization. Vulcanization and mechanical property studies were also performed.

Chiral aldehyde catalysis enables direct asymmetric α-substitution reaction of N-unprotected amino acids with halohydrocarbons.

The direct catalytic α-hydrocarbylation of readily available amino acids with halohydrocarbons is one of the most straightforward methods leading to α,α-disubstituted non-proteinogenic α-amino acid compounds. However, all the reported methodologies depend on N-protected amino acids as starting materials. Herein, we report on three highly efficient aldehyde-catalyzed direct α-hydrocarbylations of N-unprotected amino acid esters with aryl-, allyl-, and benzyl halides. By promoting a simple chiral BINOL-aldehyde catalyst or combining catalysts of a chiral aldehyde and Lewis acid ZnCl2, the asymmetric α-arylation, α-allylation, and α-benzylation of amino acid esters with the corresponding halohydrocarbons proceed smoothly, producing α,α-disubstituted α-amino acids in moderate-to-high yields and good-to-excellent enantioselectivities. The asymmetric α-arylation reaction can be applied in the formal synthesis of the clinical candidate compound (+)-AG-041R. Based on the results given by control experiments, three reaction models are proposed to illustrate the stereoselective-control outcomes.