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Commercial disinfectants are routinely used to decontaminate surfaces where microbes are expected and unwelcome. Several disinfectants contain quaternary ammonium salts, or "quats", all being derived from ammonium. Quaternary alkyl dimethyl benzyl ammonium chloride or bromide disinfectants are widely available. These compounds are effective in reducing or eliminating bacteria on contaminated nonporous surfaces. A unique benzyl derived boronium salt with strong detergent action has been developed. It demonstrated 4-8X greater antibacterial activity against 3 different bacteria when compared to an equal concentration of a commercial quant disinfectant solution containing alkyl dimethyl benzyl ammonium chloride and alkyl dimethyl ethylbenzyl ammonium chloride. Antibacterial effectiveness of each agent was determined by the minimum inhibitory concentration (MIC) method. [ABSTRACT FROM AUTHOR]

The article discusses the chemical behavior of 1-(2-Chloroethyl)-4-hydroxymethylpyrazoles using distillation process. It mentions that the obtained 4-hydroxymethylpyrazoles were isolated by distillation only in 20-30% yield except for compound whose yield reached 75%. It examines the abnormal behavior of the compounds under distillation in a series of N-alkyl-4-hydroxymethylpyrazoles.

Alkylation of p-tert-butylcalix[4]arenes with alkyl bromides or iodides under microwave irradiation affords mostly the corresponding distal disubstituted ethers, whereas in case of alkyl chlorides reasonable yields of monoethers were achieved. [Copyright &y& Elsevier]

Direct inhibition of GPX4 requires covalent modification of the active-site selenocysteine. While phenotypic screening has revealed that activated alkyl chlorides and masked nitrile oxides can inhibit GPX4 covalently, a systematic assessment of potential electrophilic warheads with the capacity to inhibit cellular GPX4 has been lacking. Here, we survey more than 25 electrophilic warheads across several distinct GPX4-targeting scaffolds. We find that electrophiles with attenuated reactivity compared to chloroacetamides are unable to inhibit GPX4 despite the expected nucleophilicity of the selenocysteine residue. However, highly reactive propiolamides we uncover in this study can substitute for chloroacetamide and nitroisoxazole warheads in GPX4 inhibitors. Our observations suggest that electrophile masking strategies, including those we describe for propiolamide- and nitrile-oxide-based warheads, may be promising for the development of improved covalent GPX4 inhibitors. [ABSTRACT FROM AUTHOR]

Quaternary ammonium compounds (Quats) are a large class of permanently charged cationic chemicals that are used in a variety of consumer and industrial products for their antimicrobial properties. Didecyl dimethyl ammonium chloride (DDAC) and alkyl (C12, C14, C16) dimethyl benzyl ammonium chloride (C12–C16 ADBAC) are frequently used as active ingredients in antimicrobials and are the focus of the current hazard assessment. Robust toxicology databases exist for both DDAC and C12–C16 ADBAC; however, the majority of available studies for DDAC and C12–C16 ADBAC are unpublished, but have been submitted to and reviewed by regulatory agencies (i.e., EPA and European Chemicals Agency) to support antimicrobial product registration. With the objective of contributing to public understanding of the robust and complete toxicology database available for DDAC and C12–C16 ADBAC, a comprehensive review was conducted using available peer-reviewed literature and unpublished data submitted to and summarized by regulatory agencies. A review of available literature indicates that DDAC and C12–C16 ADBAC have similar hazard profiles. Both DDAC and C12–C16 ADBAC are poorly absorbed via the oral and dermal exposure routes (≤10%), are not systemically distributed, and are primarily excreted in feces. DDAC and C12–C16 ADBAC are not dermal sensitizers, are not specific developmental or reproductive toxicants, are not carcinogenic or genotoxic, and do not cause systemic toxicity. DDAC and C12–C16 ADBAC are irritating/corrosive to skin at high concentrations, and are acutely toxic via the oral, dermal (C12–C16 ADBAC only), and inhalation exposure routes; however, both DDAC and C12–C16 ADBAC are considered non-volatile and are not readily aerosolized. Both DDAC and C12–C16 ADBAC can cause toxicity in repeated dose oral toxicity studies with no-observed-adverse-effect levels ranging from 10 to 93.1 mg/kg-day for DDAC and 3.7–188 mg/kg-day for C12–C16 ADBAC in subchronic and chronic studies conducted with beagles, mice, and rats. The toxicological effects associated with reported lowest-observed-adverse-effect levels for both DDAC and C12–C16 ADBAC are consistently characterized by reduced food consumption, reduced mean body weight, reduced body weight gain, and local irritation. These effects are consistent with the mode of action of an irritating/corrosive chemical. Based upon currently available data, the main concern associated with exposure to DDAC and C12–C16 ADBAC is local effects through irritation. • Robust toxicology databases exist for both DDAC and C12–C16 ADBAC. • DDAC/C12–C16 ADBAC are poorly absorbed via the oral and dermal exposure routes. • DDAC/C12 – C16 ADBAC are dermal irritants and can be acutely toxic. • DDAC/C12–C16 ADBAC are not dermal sensitizers and do not cause systemic toxicity. • The main hazard concern for DDAC/C12–C16 ADBAC is local effects through irritation. [ABSTRACT FROM AUTHOR]

• A challenging palladium-catalyzed C(sp3)–P(III) bond formation reaction. • Differential alkyl-substituted phosphines afforded under mild and easily accessible condition. • Acylphosphine as a practical phosphorus source in C P bond formation reaction. Palladium-catalyzed C(sp3)–P(III) bond formation reaction for alkyl substituted phosphines preparation was developed. In this reaction, various alkyl bromides and limited alkyl chlorides reacted with acylphosphine under relative mild and easily accessible condition, and differential phosphines were afforded in good yields. This reaction made up the application of palladium catalysis in C(sp3)–P(III) bond formation, and indicated a practical application of acylphosphine as a phosphination reagent. [ABSTRACT FROM AUTHOR]

• Step-economical synthesis. • Metal-free conditions. • Without super acid or base. • Simple and widely available starting materials. • Avoidance of over-oxidation. An efficient and step-economical access to sulfoxides from thiols and alkyl halides in the presence of I 2 O 5 and DBU via direct oxidative couplings is described here. It is the first case that combined Williamson sulfide synthesis and subsequent sulfide oxidation into one step manipulation for sulfoxides preparation. This protocol features wide substrate scope, mild and metal-free conditons, the use of naturally abundant starting materials and avoidance of over-oxidation. [ABSTRACT FROM AUTHOR]

1,4-Bis(chloromethyl)-and 1,4-bis(bromomethyl)cubanes were synthesized by the reactions of triphenylphosphine with CCl4 and NBS, respectively. The structures of the compounds were studied by X-ray diffraction analysis. [ABSTRACT FROM AUTHOR]

• A novel Ti(IV) complexes with fluorinated 2-hydroxymethylphenoles were synthesized. • Complexes activated by alkylaluminum chlorides and MgBu 2 catalyzed UHMWPE formation. • The most active pre-catalysts contain bis-(trifluoromethyl)-carbinol fragment. • The UHMWPE powders were solid-state processed into high strength and high modulus oriented films. A series of titanium (IV) complexes 3a–g stabilized by fluorinated derivatives of 2-hydroxymethylphenol have been synthesized; their composition and structure have been confirmed by NMR, IR-spectroscopy and elemental analysis. The structures of compounds 3c , 3f and 3g have been unambiguously established by X-ray diffraction study. The complexes in the presence of a binary cocatalysts {alkyl aluminum chloride + MgBu 2 } catalyze ethylene polymerization to afford Ultra High Molecular Weight Polyethylene (UHMWPE). The effects of substituents in the ligands on the catalytic activity and properties of the obtained polymer – molecular weight, DSC melting behavior, and morphology of nascent reactor powders have been investigated. UHMWPE samples were processed by a solid-state uniaxial deformation into high-strength (up to 2.65 GPa) and high-modulus (over 140 GPa) oriented film tapes, which indirectly indicates a low degree of entanglements between the macromolecular chains. [ABSTRACT FROM AUTHOR]

In this study, a novel ionic liquid-modified magnetic mesoporous silica supported tungstate (Fe 3 O 4 @MCM@IL-WO 4 =) with core–shell structure is prepared, characterized and applied as recoverable catalyst in the green oxidation of alcohols. The magnetic mesoporous Fe 3 O 4 @MCM material was prepared through surfactant directed modification of magnetic iron oxides with tetramethoxysilane. The Fe 3 O 4 @MCM@IL-WO 4 = nanocatalyst was then prepared via chemical attachment of alkyl imidazolium chloride on Fe 3 O 4 @MCM followed by treatment with sodium tungstate. This catalyst was characterized using FT-IR spectroscopy, TG, EDX, low-angle and wide-angle PXRD, SEM, VSM and nitrogen adsorption-desorption analyses. The Fe 3 O 4 @MCM@IL-WO 4 = was applied as powerful catalyst in the green oxidation of alcohols using hydrogen peroxide oxidant under ultrasonic conditions. The corresponding carbonyl products were obtained in high yield and selectivity. The reusability, recoverability and durability of this catalyst have also been studied under applied conditions. Synthesis, characterization and catalytic application of a novel ionic liquid-modified magnetic mesoporous silica supported tungstate (Fe3O4@MCM@IL-WO4 =) are developed under ultrasonic conditions. Image 1 • A novel magnetic mesoporous silica supported ionic liquid/tungstate complex (Fe 3 O 4 @MCM@IL-WO 4 =) was prepared. • This was characterized using several tecniques such as FT-IR, TGA, SEM, VSM, PXRD and EDX. • This nanomaterial was applied as an efficient nanocatalyst for the oxidation of alcohols. • The recoverability, reusability and stability of the catalyst were also studied under applied conditions. [ABSTRACT FROM AUTHOR]

Sulfur‐containing polymers and poly(ionic liquid)s are emerging macromolecules with unique properties and applications. This article shows the first integration of these two polymer families, leading to materials with a unique combination of properties. The synthetic strategy toward sulfur‐containing poly(ionic liquid)s involves first the copolymerization of elemental sulfur with 4‐vinylbenzyl chloride and subsequent quaternization of the alkyl chloride group using N‐methyl imidazole. The synthetic pathway is completed by the anion exchange reaction of the poly(sulfur‐co‐4‐vinylbenzyl imidazolium chloride) by a sulphonamide anion. The obtained polymers are fully characterized by NMR, FTIR, SEC, DSC, and TGA. The sulfur poly(ionic liquid)s combine some properties related to its poly(ionic liquid) nature, such as anion‐dependent solubility (water vs organic solvents) and high ionic conductivity as well as properties related to its sulfur content, such as redox activity. Sulfur‐containing polymers and poly(ionic liquid)s are emerging macromolecules with unique properties and applications. This article presents the first integration of these two polymer families, leading to sulfur poly(ionic liquid)s with a unique combination of properties such as tuneable solubility, ionic conductivity, and redox properties. [ABSTRACT FROM AUTHOR]

The article presents abstracts on topics related to studies on cyclopropenium ion including the conversion of alcohols into alkyl chlorides, the Beckmann rearrangement of ketoximes, and the development of cyclopropenium ion activated cyclodehydration of 1,4- and 1,5-diols.

An abstract of the article "The Copper-Catalyzed Suzuki-Miyaura Coupling of Alkylboron Reagents: Disproportionation of Anionic (Alkyl)( (alkoxy)borates to Anionic Dialkylborates Prior to Transmetalation" by P. Basnet, S. Thapa and colleagues is presented.

The title reaction is achieved in the presence of a typical iridium photocatalyst and various substrates are tolerable. [ABSTRACT FROM AUTHOR]

The reaction has a broad substrate scope and tolerates diverse functional groups. [ABSTRACT FROM AUTHOR]

Following a scalable procedure alkyl chlorides equipped with a quinoline amide directing group are cross-coupled with various terminal alkynes to afford internal alkynes in high yields. [ABSTRACT FROM AUTHOR]

The front cover image, provided by Torben Rogge, Ruhuai Mei and Lutz Ackermann, illustrates the synthetic utility of cobalt ‐ catalyzed C – H arylations by oxazoline assistance at ambient temperature. The catalytic system derived from inexpensive Co(acac)2 and an N ‐ heterocyclic carbene enabled C – H arylations with ample scope, and proved applicable to difficult C – H alkylations with unactivated primary and secondary alkyl chlorides. The power of the C – H arylation strategy was reflected by C – H activation at 23 °C, and late ‐ stage diversification to access bioactive biaryls. Details can be found in the full paper on pages 2443 – 2448 (R. Mei, L. Ackermann, Adv. Synth. Catal. 2016, 358, 2443 – 2448; DOI: 10.1002/adsc.201600384). [ABSTRACT FROM AUTHOR]

An abstract of the study "Iron-Mediated Inter- and Intramolecular Reductive Cross-Coupling of Unactivated Alkyl Chlorides With Aryl Bromides" by Z. Li and colleagues is presented.

Fully substituted stereocenters are highly enantioselectively generated by photoinduced copper-catalyzed coupling of readily available racemic tertiary alkyl chloride electrophiles with various amines. [ABSTRACT FROM AUTHOR]

An abstract of the article "Regioselective Synthesis of Carbonyl-Containing Alkyl Chlorides via Silver-Catalyzed Ring-Opening Chlorination of Cycloalkanols" by Feng-Qing Huang and colleagues is presented.

An abstract of the article "Photoinduced, Copper-Catalyzed Carbon-Carbon Bond Formation with Alkyl Electrophiles: Cyanation of Unactivated Secondary Alkyl Chlorides at Room Temperature" by Tanvi S. Ratani is presented.

The reaction fails for trifluoromethylated tertiary alkyl bromides and gives only poor yields for trifluoromethylated primary alkyl chlorides (not shown). [ABSTRACT FROM AUTHOR]

The lithium dispersion reductive lithiation of phenyl thioethers, alkyl chlorides, acrolein diethyl acetal, and isochroman is investigated. [ABSTRACT FROM AUTHOR]

The reaction succeeds using a 2-pyridyl group as the directing group, but is delivered with low or no yield when switching to a pyrazole or imine group. [ABSTRACT FROM AUTHOR]

A correction to the article "Cobalt-Catalyzed Directed Alkylation of Olefinic C-H Bond with Primary and Secondary Alkyl Chlorides" that was published in the previous issue is presented.

A one-pot three-component reaction between alkyl chlorides, sodium azide and terminal alkynes is also reported. [ABSTRACT FROM AUTHOR]

The first example of Rh-catalyzed borylation of unactivated alkyl chlorides is given. [ABSTRACT FROM AUTHOR]

Additionally an analog with a longer alkyl chain is synthesized. [ABSTRACT FROM AUTHOR]

The title reaction proceeds under ambient temperature and low catalyst loading with excellent chemo- and site-selectivities for a broad substrate scope. [ABSTRACT FROM AUTHOR]