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A series of new substituted derivatives of N-alkyl-4-aryl-2-aroylhydrazylidene-4-oxobutanamides were synthesized via the opening of the furan ring in substituted 3-N-5-aryl-2-oxofuran-3(2H)-ylidene-4-R1-benzohydrazides under the action of various alkylamines. The in vivo analgesic activity and acute toxicity of the synthesized compounds were assessed to show that they have a pronounced analgesic activity and are almost nontoxic. [ABSTRACT FROM AUTHOR]

Convenient synthesis of P(O)CH2N-substituted bis- and tris-phosphorus-containing amines using two- and three-component systems have been developed. Methods for the synthesis of new bis- and tris-aminomethylating reagents are presented. Esters of trivalent phosphorus acids react with paraformaldehyde, alkylamines or N-substituted bis(alkoxymethyl)amines, as well as tris(butoxymethyl)amine to give new P(O)CH2N-substituted bis- and tris-phosphorus-containing amines. The resulting compounds are of interest as water-soluble polydentate ligands and effective extractants, as well as promising biologically active substances. [ABSTRACT FROM AUTHOR]

Based on individual exo- and endo-isomers of tricyclo[5.2.1.02.6]deca-2-carboxylic acid, various nitrogencontaining derivatives were synthesized: amides, thioamides, amines, alkylamines, amidines. Antiviral properties tested. [ABSTRACT FROM AUTHOR]

Alkylamines form the backbone of countless nitrogen‐containing small molecules possessing desirable biological properties. Despite advances in amine synthesis through transition metal catalysis and photoredox chemistry, multicomponent reactions that leverage inexpensive materials to transform abundant chemical feedstocks into three‐dimensional α‐substituted alkylamines bearing complex substitution patterns remain scarce. Here, we report the design of a catalyst‐free electroreductive manifold that merges amines, carbonyl compounds and carbon‐based radical acceptors under ambient conditions without rigorous exclusion of air and moisture. Key to this aminative carbofunctionalization process is the chemoselective generation of nucleophilic α‐amino radical intermediates that readily couple with electrophilic partners, providing straightforward access to architecturally intricate alkylamines and drug‐like scaffolds which are inaccessible by conventional means. [ABSTRACT FROM AUTHOR]

Reductive N‐11C‐methylation using [11C]formaldehyde and amines has been used to prepare N‐11C‐methylated compounds. However, the yields of the N‐11C‐methylated compounds are often insufficient. In this study, we developed an efficient method for base‐free reductive N‐11C‐methylation that is applicable to a wide variety of substrates, including arylamines bearing electron‐withdrawing and electron‐donating substituents. A 2‐picoline borane complex, which is a stable and mild reductant, was used. Dimethyl sulfoxide was used as the primary reaction solvent, and glacial acetic acid or aqueous acetic acid was used as a cosolvent. While reductive N‐11C‐methylation efficiently proceeded under anhydrous conditions in most cases, the addition of water to the reductive N‐11C‐methylation generally increased the yield of the N‐11C‐methylated compounds. Substrates with hydroxy, carboxyl, nitrile, nitro, ester, amide, and phenone moieties and amine salts were applicable to the reaction. This proposed method for reductive N‐11C‐methylation should be applicable to a wide variety of substrates, including thermo‐labile and base‐sensitive compounds because the reaction was performed under relatively mild conditions (70°C) without the need for a base. [ABSTRACT FROM AUTHOR]

Alkylamines with different chain lengths including n-butylamine, n-hexylamine, and n-octylamine, are applied to regulate the CsPbIBr2 perovskite film quality by strain engineering. The status of residual strains is controllably modulated, resulting in improved efficiency and stability of carbon-based hole-transport-material free CsPbIBr2 perovskite solar cells. [ABSTRACT FROM AUTHOR]

On Earth and beyond, organic chemistry often occurs in the presence of water within environments that deviate drastically from ambient conditions (25 °C and 1 bar). Accurately predicting aqueous organic reaction pathways is crucial toward understanding planetary scale processes such as the cycling of elements crucial for life (e.g., carbon and nitrogen). Advanced thermodynamic modeling can be utilized to determine the favorability of various organic reactions based on geologically relevant ranges of temperature and pressure, as well as compositional variables (e.g., pH). However, data that would otherwise allow for a diversity of organic compounds and environmental conditions to be modeled are sparse and rarely tested with experiments, particularly with regard to organic-nitrogen compounds. In this work, we develop a framework to estimate thermodynamic properties at ambient conditions that can then be extrapolated across ranges of temperature and pressure for aqueous primary, secondary, and tertiary amines and aminiums (protonated amines), specifically those structures containing linear alkyl chains and benzyl functional groups. We also performed hydrothermal experiments (250 °C, ∼40 bar) involving reactions of methylamines to test our resulting thermodynamic models, and we compare our models for other alkylamines and benzylamines to previous empirical measurements from the literature. Specifically, we use existing thermodynamic data along with our estimates at ambient conditions in combination with a variety of existing extrapolation methods related to the revised Helgeson-Kirkham-Flowers (HKF) equations of state to generate temperature- and pressure-dependent predictions of acid dissociation constants (i.e., p K a values) that strongly agree with previous empirical measurements. We use similar methods to predict product distributions for reactions involving primary, secondary, and tertiary amines/aminiums, as well as ammonia/ammonium and corresponding alcohols whose collective distributions depend on reversible substitution reactions. Our predictions are in good agreement with our experimental results involving the methylamine reaction system as well as previous experiments involving the benzylamine reaction system, for which we also produced thermodynamic estimates involving benzyl alcohol. The agreement between independent theoretical predictions and experimental measurements suggests that our estimated properties can be applied to modeling amine chemistry in other experimental and natural aqueous systems that range in temperature and pressure, providing new tools for planetary exploration. [ABSTRACT FROM AUTHOR]

Micellar systems have the advantage of being easily prepared, cheap, and readily loadable with bioactive molecular cargo. However, their fundamental pitfall is poor stability, particularly under dilution conditions. We propose to use simple quaternary ammonium surfactants, namely, hexadecylamine (HDA) and hexadecylpyridinium (HDAP), together with tripolyphosphate (TPP) anion, to generate ionotropically stabilized micelles capable of drug delivery into cancer cells. optimized mixed HDA/HDAP micelles were prepared and stabilized with TPP. Curcumin was used as a loaded model drug. The prepared nanoparticles were characterized by dynamic light scattering, infrared spectroscopy, transmission electron microscopy, and differential scanning calorimetry. Moreover, their cellular uptake was assessed using flow cytometry and confocal fluorescence microscopy. The prepared nanoparticles were found to be stable under dilution and at high temperatures and to have a size range from 139 nm to 580 nm, depending on pH (4.6-7.4), dilution (up to 100 times), and temperature (25 – 80 °C). They were effective at delivering their load into cancer cells. Additionally, flow cytometry indicated the resulting stabilized micellar nanoparticles to be non-cytotoxic. The described novel stabilized micelles are simple to prepare and viable for cancer delivery. [ABSTRACT FROM AUTHOR]

We describe a multicomponent reaction between isatoic anhydrides, alkylamines and benzylic alcohols using Pd(II)/TPPMS catalyst with cocatalytic Cu(II) salt in water. This cascade reaction involves the catalytic dehydrogenation of benzyl alcohol to benzaldehyde under aerobic conditions, followed by cyclocondensation with in situ generated 2‐aminobenzamides, allowing rapid access to 2,3‐dihydroquinazolin‐4(1H)‐ones (DHQs). This practical method enables direct access to a series of DHQs without strong bases and hazardous oxidants. Mechanistic studies reveal that the multicomponent reaction is first order with respect to the concentrations of benzyl alcohol and catalysts, and proceeds independently of the concentration of the 2‐aminobenzamide intermediate. [ABSTRACT FROM AUTHOR]

This article discusses a new method for synthesizing primary amines through benzylic C-H carbamation. The researchers tested various ligands, solvents, and oxidants, finding that the BOX ligand L1, acetonitrile, and NFSI were the most efficient. The method was successfully applied to different substrates, including heterocycles and common pharmacophores. The authors highlight the advantages of their method, such as the use of a cheap catalyst and the ability to easily deprotect the Boc-protected amines. They also demonstrate the relevance of their method to medicinal chemistry by synthesizing two pharmaceuticals, Sensipar and Zoloft. Overall, this method provides a sustainable option for incorporating primary amines into pharmaceutical and agrochemical building blocks. [Extracted from the article]

Treatment of 3-bromo-6-chloroimidazo[1,2-b]pyridazine with a variety of 1° or 2° alkylamines (2.0 equiv) with CsF (1.0 equiv), and BnNEt3Cl (10 mol %) in DMSO at 100 °C (24 hours) gave the corresponding C-6 aminated products in excellent isolated yields (79–98%; ave. yield = 92%). These conditions worked well for simple unfunctionalized 1° alkylamines, 1° amines with methylene- or ethylene-linked aromatic or heteroaromatic functionality (e.g. benzene, thiophene, furan, indole, and pyridine), and 2° alkylamines such as pyrrolidine, morpholine, and piperidine were also well tolerated. The method is cost-effect, providing C-6 aminated products in consistently high yields, while at the same time utilizing far less toxic fluoride (10 fold less), than previous fluoride-promoted aminations. [ABSTRACT FROM AUTHOR]

The reaction of (1,2-dibromoethyl)(diphenyl)phosphine oxide with CH-acids (acetylacetone, acetoacetic ester, and malonic ester) in the presence of sodium hydroxide has afforded diphenylphosphoryl-substituted cyclopropanes in high yield. It has been shown that the reaction of (1,2-dibromoethyl)(diphenyl)phosphine oxide with primary arylamines leads to the formation of bis(phosphine oxides), in contrast to alkylamines which lead to phosphoryl-substituted aziridines. [ABSTRACT FROM AUTHOR]

α‐Aminoalkylation of sulfonylarenes with alkylamines was found to be induced by photoirradiation. Here various types of alkylamines, such as trialkylamines, dialkylamines, N,N‐dialkylanilines and N‐alkylanilines as well as sulfonylarenes containing an azole, azine, heterole or benzene ring are available. The reaction proceeds through a homolytic aromatic substitution (HAS) process consisting of addition of an α‐aminoalkyl radical to a sulfonylarene and elimination of the sulfonyl radical to give the α‐arylalkylamine, where photoirradiation is considered to induce homolysis of sulfonylarenes leading to the generation of α‐aminoalkyl radicals that make a radical chain operative. [ABSTRACT FROM AUTHOR]

Microbial enzymes are versatile, cost-effective, and sustainable tools, making them a preferred choice for enzymatic processes. Santema et al. harnessed AlphaFold, a cutting-edge structure prediction tool, to discover new thermophilic monoamine oxidases (MAO) that could be relevant for drug development and use in biotechnology fields. The new enzyme displays thermal robustness, offering a unique structure-to-function profile compared to known MAOs. This bacterial enzyme, paired with recent advancements in enzyme engineering, has the potential to meet the biotech sector's need for customized enzymes. [ABSTRACT FROM AUTHOR]

In this paper, we describe the synthesis and the (chir)optical properties of a novel series of circularly polarized luminescent emitters. These molecules involve a compact single benzene‐based donor‐acceptor fluorophore composed of two cyclic alkylamines as electron donors and a phthalonitrile moiety as electron acceptor linked to a configurationally stable BINOL acting as a chiral perturbation unit. These new compounds display fair quantum yields (up to 66%) with emission maxima around 500 nm in toluene solutions, and the study of their chiroptical properties has shown that the cyclic alkylamine's ring size affects significantly the luminescence dissymmetry factors, reaching 2.2 × 10−3 for the larger cyclic alkylamine moieties. [ABSTRACT FROM AUTHOR]

Spirocyclic tetrahydronaphthyridines (THNs) are valuable scaffolds for drug discovery campaigns, but access to this 3D chemical space is hampered by a lack of modular and scalable synthetic methods. We hereby report an automated, continuous flow synthesis of α-alkylated and spirocyclic 1,2,3,4-tetrahydro-1,8-naphthyridines ("1,8-THNs"), in addition to their regioisomeric 1,6-THN analogues, from abundant primary amine feedstocks. An annulative disconnection approach based on photoredox-catalysed hydroaminoalkylation (HAA) of halogenated vinylpyridines is sequenced in combination with intramolecular SNAr N-arylation. To access the remaining 1,7- and 1,5-THN isomers, a photoredox-catalysed HAA step is telescoped with a palladium-catalysed C–N bond formation. Altogether, this provides a highly modular access to four isomeric THN cores from a common set of unprotected primary amine starting materials, using the same bond disconnections. The simplifying power of the methodology is illustrated by a concise synthesis of the spirocyclic THN core of Pfizer's MC4R antagonist PF-07258669. Spirocyclic tetrahydronaphthyridines (THNs) are valuable structural motifs in medicinal chemistry, but the modular and scalable synthesis of this specific motif remains challenging. Here, the authors develop an automated and continuous flow synthesis of 1,8-THN and 1,6-THN analogues based on photoredox-catalysed hydroaminoalkylation, demonstrating the concise synthesis of the spirocyclic THN core of Pfizer's MC4R antagonist PF-07258669. [ABSTRACT FROM AUTHOR]

In this article we report that a cationic version of Akiba's BiIII complex catalyzes the reduction of amides to amines using silane as hydride donor. The catalytic system features low catalyst loadings and mild conditions, en route to secondary and tertiary aryl‐ and alkylamines. The system tolerates functional groups such as alkene, ester, nitrile, furan and thiophene. Kinetic studies on the reaction mechanism result in the identification of a reaction network with an important product inhibition that is in agreement with the experimental reaction profiles. [ABSTRACT FROM AUTHOR]

Polyamines are positively charged alkylamines ubiquitous among eukaryotes, prokaryotes, and archaea. Humans obtain polyamines through dietary intake, metabolic production, or uptake of polyamines made by gut microbes. The polyamine biosynthetic pathway used by most gut microbes differs from that used by human cells. This alternative pathway employs carboxyspermidine dehydrogenase (CASDH), an enzyme with limited characterization. Here, we solved a 1.94 Å X-ray crystal structure of Bacteroides fragilis CASDH by molecular replacement. BfCASDH is composed of three domains with a fold similar to saccharopine dehydrogenase but with a distinct active site arrangement. Using steady-state methods, we determined kcat and kcat/Km for BfCASDH and Clostridium leptum CASDH using putrescine, diaminopropane, aspartate semi-aldehyde, NADH, and NADPH as substrates. These data revealed evidence of cooperativity in BfCASDH. Putrescine is the likely polyamine substrate and NADPH is the coenzyme used to complete the reaction, forming carboxyspermidine as a product. These data provide the first kinetic characterization of CASDH —a key enzyme in the production of microbial polyamines. [ABSTRACT FROM AUTHOR]

The production of N,N-dialkyl arylamines is relevant for a range of high-value materials such as pharmaceuticals, agrochemicals and organic materials. In general, these molecules are assembled via multiple pre-functionalization steps of the aromatic compound and a subsequent cross-coupling with the arylamine under harsh conditions. In this manuscript, we develop a more sustainable and efficient method for the direct C–H amination of arenes and alkylamines using Ru(bipy)32+ entrapped in the supercages of a faujasite support (CBV-100). This creates a heterogeneous photocatalyst that can be used under visible light irradiation. Furthermore, the mesomeric and/or inductive effects of the substituent groups on the arene coupling partner are thoroughly investigated using Hammett plots, leading to a rationally guided solvent selection (HFIP or CH3CN). Using reduced reaction temperatures (<0 °C) drastically improves the product yield, while suppressing the generation of side products. [ABSTRACT FROM AUTHOR]

The densities, ρ, and the speeds of sound, u, for binary liquid mixtures containing propylene glycol monopropyl ether (PGMPE) and n- butylamine (BA), dibutylamine (DBA) or tributylamine (TBA) have been measured as a function of composition using a vibrating tube densimeter and sound analyzer Anton-Paar model DSA-5000 at temperatures 288.15, 298.15 and 308.15 K and atmospheric pressure. From these data excess molar volumes, VmE, the thermal expansion coefficient, αE, and deviations in isentropic compressibility, Δκs, have been calculated.. The VmE values are negative over the whole mole fraction range for the systems propylene glycol monopropyl ether + n-butylamine, and dibutylamine, and positive for the system propylene glycol monopropyl ether + tributylamine. whereas the Δκs values are negative over the entire range of composition for all mixtures with the exception of tributylamine. Also, in the present study, thermophysical parameters such as apparent molar volume,vФ,i, and apparent molar isentropic compressibility, Kφ,i are studied for the PGMPE with BA, DBA or TBA. The results reveal the dominance of ether -- BA or DBA as compared to ether --TBA interactions which are found to increase with elevation of temperature but decrease with increasing the chain length of alkylamine. Further, the deviation of the speeds of sound uD from their ideal values uid in an ideal mixture have been calculated for all measured values of mole fraction x1. Sign and magnitude of VmE, Δκs and uD with respect to the composition and temperature have been used to analyze the mixing behavior of the components. [ABSTRACT FROM AUTHOR]

Alkyl diethanolamines are a group of compounds commonly used as antistatic agents in plastic food packaging materials. These additives and their possible impurities have the ability to transfer into the food; hence, the consumer may be exposed to these chemicals. Recently, scientific evidence of unknown adverse effects associated with these compounds was reported. N,N-bis(2-hydroxyethyl)alkyl (C8-C18) amines as well as other related compounds and their possible impurities were analyzed in different plastic packaging materials and coffee capsules using target and non-target LC-MS methods. N,N-bis(2-hydroxyethyl)alkyl amines, precisely, C12, C13, C14, C15, C16, C17 and C18, 2-(octadecylamino)ethanol and octadecylamine, among others, were identified in most of the analyzed samples. It should be emphasized that the latter compounds are not listed in the European Regulation 10/2011 and 2-(octadecylamino)ethanol was classified as high toxicity according to Cramer rules. Migration tests were carried out in foods and in the food simulants Tenax and 20% ethanol (v/v). The results showed that stearyldiethanolamine migrated into the tomato, salty biscuits, salad and Tenax. Lastly, as a crucial step in the risk assessment process, the dietary exposure to stearyldiethanolamine transferred from the food packaging into the food was determined. The estimated values ranged from 0.0005 to 0.0026 µg/kg bw/day. [ABSTRACT FROM AUTHOR]

Radicals can be formed expeditiously through the direct irradiation of an electron donor‐acceptor (EDA) complex. Herein, we show a photocatalyst‐free strategy for gem‐difluoroalkenes synthesis realized by photo‐irradiation of the EDA complexes, which can be generated in situ between N‐alkylpyridinium salts and Hantzsch ester without any other additives. A wide variety of readily available alkylamines underwent deaminative defluoroalkylation to provide the corresponding gem‐difluoroalkenes. This reaction system exhibits high reactivity and good functional group tolerance and provides a practical and effective entry to a broad range of α‐alkyl‐substituted gem‐difluoroalkenes. [ABSTRACT FROM AUTHOR]

The nucleophilic substitution of organohalides with alkylamines is one of the most heralded reactions in synthetic chemistry. However, the resulting halide anions are often wasted in routine workup experiments and not fully utilized. Herein, we report a halogen recycling strategy for radical aminohalogenation of maleimides with XCH2CH2X (X = Cl, Br) and alkylamines with excellent functional group compatibility. The strategy's excellent generality is demonstrated by 38 aminohalogenated products, twofold aminochlorination, and late‐stage vinylchlorination of nortriptyline. [ABSTRACT FROM AUTHOR]

Hydrogen gas production generated from carbon-free molecules while utilizing solar energy provided a pathway for zero carbon emission energy. In photocatalytic hydrogen gas production, alcohol and oxygenated compounds as sacrificial agents are often added to accelerate the water splitting process while simultaneously decomposing to form H2 and CO2. However, the generation of CO2 requires an additional measure to curb carbon from being released into the atmosphere. This study evaluated the performance of TiO2 photocatalysts to generate hydrogen from NH3 solution as carbon-free molecules. The investigation is extended to alkylamines compounds as sacrificial agents. H2 is linearly produced from NH3 when using Pd/TiO2; however, the rate is reduced after a prolonged photocatalytic reaction. Alkylamines molecules are more susceptible for H2 production than NH3, with the reactivity increased from NH3 < triethylamine < diethylamine < ethylamine. Comparative analysis was also conducted on the amount of H2 and CO2 gases released from alkylamines and alcohols to indicate nitrogen-containing compounds viability as sacrificial agents for carbon-emission free sacrificial agents in photocatalytic water splitting reaction. [ABSTRACT FROM AUTHOR]

A systematic competitive evaluation of the DalPhos ligand family in nickel‐catalyzed N‐arylation chemistry is reported, involving primary (linear and branched) and secondary alkylamines, as well as a primary five‐membered heteroarylamine (aminopyrazole), in combination with a diverse set of test electrophiles and bases (NaOtBu, K2CO3, DBU/NaTFA). In addition to providing optimal ligand/catalyst identification, and bringing to light methodology limitations (e. g. unwanted C−O cross‐coupling with NaOtBu), our survey enabled the development of the first efficient catalyst system for heteroatom‐dense C−N cross‐coupling of aminopyrazoles and related nucleophiles with (hetero)aryl chlorides by use of an amine 'dual‐base' system. [ABSTRACT FROM AUTHOR]

A meaningful copper‐catalyzed chemo‐selective oxidative alkylamination of maleimides with secondary alkyl amines and simple alkanes has been developed. This transformation exhibits excellent compatibility with an array of polyfunctionalized organic amines and inactivated alkanes, modular synthesis of 3‐carbo‐4‐amino maleimides under simple, and efficient catalytic systems. Detailed mechanistic studies support the formation of 3‐amino maleimides and alkyl radical intermediates and their subsequent radical alkylation in the reaction process. [ABSTRACT FROM AUTHOR]

Different long-chain primary alkylamines such as octylamine, dodecylamine, tetradecylamine, hexadecylamine or octadecylamine were used to stabilize Ni-NiO nanoparticles (metal:stabilizer ratio of 1:10) by an organometallic method in organic medium to evaluate their effect on the microstructural and magnetic properties. The Ni-NiO stabilized nanoparticles were characterized by Fourier transformed infrared (FT-IR), X-ray photoelectron spectroscopy (XPS), conventional transmission electron microscopy (TEM), high resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD) and dynamic light scattering (DLS). The results indicated an adequate stabilization of Ni nanoparticles with the different primary alkylamines. The semi-quantitative analysis suggests that Ni surface composition is a combination of the metallic state with NiO, NiOOH and NiO, but the chain length modified the content and proportion of these compounds. The highest Ni metallic state (57.2 at. %) was obtained with tetradecylamine as stabilizer. The morphology of the samples is similar to a core–shell semi-spherical, but the particle size tends to reduce with the alkyl chain length of primary amines from 20 to 8 nm. The saturation magnetization (Ms) showed important variations depending on the surface composition, for which variable particle size and Ni metallic content were determining factors for the magnetic response. [ABSTRACT FROM AUTHOR]

Aminium radicals are attractive intermediates in synthetic chemistry that readily participate in a series of C–N bond-forming processes. Here, we briefly discuss strategies for generating aminium radicals from various precursors in the context of intermolecular alkene amination, and we highlight recent advances in aminium-radical-mediated hydroaminations of nonactivated olefins to directly approach alkylamines. 1 Introduction 2 Intermolecular Hydroamination of Nonactivated Alkenes with Alkylamines under Photoredox Catalysis 3 Intermolecular Hydroamination of Nonactivated Alkenes with Aliphatic Azides 4 Conclusions [ABSTRACT FROM AUTHOR]

A practical method for regioselective hydroarylation of unactivated γ- or δ-vinyl alkylamines has been reported, enabling facile preparation of highly value-added ε- or ζ-aryl alkylamines. The protocol employs nickel catalysis, shows high functional group tolerance and can be used for modifying bio-related molecules. [ABSTRACT FROM AUTHOR]

Catalytic carbonylations of aryl electrophiles via C(sp2)−N cleavage remains a significant challenge. Herein, we demonstrate an aminocarbonylation of aniline‐derived trialkylammonium salts promoted by visible light with a simple cobalt catalyst. The reaction proceeds under mild conditions suitable for late‐stage functionalization and is amenable to telescoped carbonylations directly from anilines. A range of alkylamines are successful partners, and alkoxycarbonylation is also demonstrated. Mechanistic studies and DFT calculations support a novel mechanism for catalytic carbonylations of aryl electrophiles involving a key visible light‐induced carbonyl photodissociation. [ABSTRACT FROM AUTHOR]

Layered TiS2 intercalated with linear alkylamines has recently attracted significant interest as a model compound for flexible n-type thermoelectric applications, showing remarkably high power factors at room temperature. The thermal and, particularly, environmental stability of such materials is, however, a still an open challenge. In this paper, we show that amine-intercalated TiS2 prepared by a simple mechanochemical process is prone to chemical decomposition through sulfur exsolution, and that the presence of molecular oxygen is likely to mediate the decomposition reaction. Through computational analysis of the possible reaction pathways, we propose that Ti-N adducts are formed as a consequence of amine groups substituting for S vacancies on the internal surfaces of the S-Ti-S layers. These findings provide insights for possible future applications of similar hybrid compounds as devices operating in ambient conditions, and suggest isolating them from atmospheric oxygen. [ABSTRACT FROM AUTHOR]

Quantum-chemical results are summarized and analyzed from studying the interactions of NH3 and alkylamines (R)nNH3–n (R = CH3, C2H5, C3H7, C4H9, and n = 1–3) with a series of protic acids of different strengths. Data are obtained on the proton affinity of alkylamines and acid anions. Energy characteristics of molecular complexes and ion pairs formed after acid–base interaction are assessed. It is proposed that the difference between the proton affinity of an acid anion and alkylamine be used to assess the degree of proton transfer in acid–base interactions. [ABSTRACT FROM AUTHOR]

The present study reported the synthesis of SnS2 nanoparticles by using a thermal decomposition approach using tin chloride and thioacetamide in diphenyl ether at 200 °C over 60 min. SnS2 nanoparticles with novel morphologies were prepared by the use of different alkylamines (namely, octylamine (OCA), dodecylamine (DDA), and oleylamine (OLA)), and their role during the synthesis was explored in detail. The synthesized SnS2 nanostructures were characterized using an array of analytical techniques. The XRD results confirmed the formation of hexagonal SnS2, and the crystallite size varied from 6.1 nm to 19.0 nm and from 2.5 to 8.8 nm for (100) and (011) reflections, respectively. The functional group and thermal analysis confirmed the presence of organics on the surface of nanoparticles. The FE-SEM results revealed nanoparticles, nanoplates, and flakes assembled into flower-like morphologies when dodecylamine, octylamine, and oleylamine were used as capping agents, respectively. The analysis of optical properties showed the variation in the bandgap and the concentration of surface defects on the SnS2 nanoparticles. The role of alkylamine as a capping agent was explored and discussed in detail in this paper and the mechanism for the evolution of different morphologies of SnS2 nanoparticles was also proposed. [ABSTRACT FROM AUTHOR]

A series of novel glycouril derivatives were synthesized through Mannich condensation of 2,8-xylylene-2,4,6,8-tetraazabicyclo[3.3.0]octane-3,7-dione with formaldehyde and alkylamines or diamines. These glycoluril derivatives may be regarded as molecular scaffolds acting as excellent receptors. [ABSTRACT FROM AUTHOR]

We herein present an example of photoinduced catalyst- and metal-free allylic defluorinative alkylation of trifluoromethyl alkenes with Katritzky salts in the presence of an easily available Hantzsch ester or Et3N. This simple method can accommodate primary alkylamines with primary and secondary carbon, delivering gem-difluoroalkenes with complex and diverse structures. In addition to the sustainable feature of being catalyst- and metal-free, the transformations also show great functional group tolerance and viable functionalization of late-stage biologically and pharmaceutically relevant molecules. [ABSTRACT FROM AUTHOR]

Recently, metal halide perovskites have attracted considerable interest as highly emissive phosphors for use in white light‐emitting diodes (WLEDs). In perovskites, the migration of halide anions between green‐emitting bromide (e.g., CsPbBr3) and red‐emitting iodide (e.g., CsPbI3) materials is one obstacle to application. Here perovskite WLEDs that do not suffer from the anion exchange problem are reported: this is done by developing green‐emitting single‐layer sheets of (RNH3)2PbI4 (R = C18H35–, C12H25–, and C8H17–) and uniting these with red‐emitting CsPbI3 perovskite quantum dots (QDs). It relies on self‐assembly from ligand‐capped CsPbI3 nanocrystals to form single‐layer sheets of (C18H35NH3)2PbI4: via judicious selection of alkylamines and alkyl acids, (RNH3)2PbI4 single‐layer sheets that exhibit bright and stable green emission with well‐defined single‐layer thickness are produced. Emission from 505, 512 to 536 nm is tuned and a narrow (<20 nm) linewidth is retained. Perovskite LEDs that produce white light with chromaticity coordinates (0.32, 0.33) and color gamut that reaches 117% National Television System Committee (NTSC) in the International Commission on Illumination (CIE) 1931 color space are demonstrated. [ABSTRACT FROM AUTHOR]

Regiodivergent alkene functionalization that produces either regioisomer starting from the same raw materials is desirable. Herein, we report a nickel‐catalyzed switchable site‐selective alkene hydroalkylation. The selection of reaction temperatures leads to protocols that provide regiodivergent hydroalkylated products starting from a single alkene substrate. This protocol allows the convenient synthesis of α‐ and β‐branched protected amines, both of which are important to the fields of pharmaceutical chemistry and biochemistry. In addition, enantioenriched β‐branched alkylamines can be accessed in a catalytic asymmetric variant. Preliminary mechanistic studies indicate that the formation of a more stable nickelacycle provides the driving force of migration. The thermodynamic and kinetic properties of different reduction elimination intermediates are responsible for the switchable site‐selectivity. [ABSTRACT FROM AUTHOR]

The ability of amino acid "customizable units" to generate structural diversity is illustrated by the conversion of 4-hydroxyproline (Hyp) units into a variety of nitrogen heterocycles. After a first common step, where the unit underwent a one-pot decarboxylation–alkylation reaction to afford 2-alkylpyrrolidines with high stereoselectivity, a divergent step was carried out. Thus, the deprotected 4-hydroxy group was used either to initiate a radical scission that afforded aliphatic β-amino aldehydes, or to carry out an elimination reaction, to give 2-alkyl-2,5-dihydro-1H-pyrroles. In the first case, the amines underwent a tandem reductive amination–cyclization to afford β-amino-δ-lactams, an efficient rigidifying unit in peptides. Different lactam N-substituents, such as alkylamines, peptides, and alkenyl chains suitable for olefin metathesis were introduced this way. In the second case, the pyrrole derivatives were efficiently converted into alkaloid and iminosugar derivatives in good global yields and with excellent stereoselectivity. [ABSTRACT FROM AUTHOR]

We reported a copper‐catalyzed vinylamination of S‐alkylisothiouronium salts with maleimide and organic amines with the assistance of FeCl3, enabling the preparation of structurally diverse aminoalkylthiolated maleimides and applying them to late‐stage modification of pharmaceuticals. Importantly, this strategy makes it possible to introduce the SCD3 functional group into the maleimide skeleton by using the prepared S‐trideuteromethyl isothiouronium iodide. Preliminary mechanistic investigation shows that FeCl3 is essential to the current multi‐component reaction by triggering S‐alkylisothiouronium salts. [ABSTRACT FROM AUTHOR]

Herein, it is shown how a proton transfer process between the organic moiety in 3D methylammonium lead halide perovskite and the introduced aliphatic alkylamines provides the basis for a fabrication route toward hybrid 3D/2D perovskites and finally purely 2D Ruddlesden–Popper (RP) perovskite phases, predominantly the n = 1 phase. Five alkylamines with varying aliphatic chain lengths, such as butylamine, octylamine, dodecylamine, hexadecylamine, and octadecylamine as antisolvents in toluene, are used, which quickly protonate during the spin‐coating deposition of thin perovskite films. Formation of hydrogen bonds between protonated alkylamines and lead halide slabs leads to mixed 3D/2D hybrid perovskites, where the ratio between the 3D and 2D phases can be adjusted by the concentration of the alkylamine containing antisolvents. Longer‐chain aliphatic alkylamines (12 carbon atoms or greater) are most prone to slice 3D perovskite into layered perovskites with efficient green emission reaching up to 38% for their photoluminescence quantum yield in films. Above a certain concentration threshold, 3D perovskite can be completely modified into 2D RP perovskite phases with crystalline orientation parallel to the substrate. The introduced facile perovskite phase modification approach provides a convenient way toward different kinds of 2D RP metal halide perovskite films with attractive optical properties. [ABSTRACT FROM AUTHOR]

N‐heterocyclic carbene‐palladium(II) amine complexes bearing primary aryl‐ or alkylamines were synthesized. The prepared complexes were characterized by single crystal X‐ray diffraction as well as NMR spectroscopy. These complexes exhibited good catalytic activities for the Buchwald‐Hartwig amination reaction of aryl chlorides to afford arylated anilines under mild conditions. All reactions were carried out in air and all starting materials were used as supplied without purification. 21 expected coupling products were obtained in moderate to high yields under optimum conditions. [ABSTRACT FROM AUTHOR]

Methyl (2Z)-[2[(diaminomethylene)amino]-4-oxothiazol-5(4H)-ylidene]acetate was obtained by the reaction of N-amidinothiourea and dimethyl acetylenedicarboxylate (DMAD) under various conditions: methanol, ethanol, acetonitrile, ethyl acetate, dioxane, acetic acid, ethanol/TsOH. The structure of the product has been proven by X-ray diffraction analysis. A series of new N-(5-R-1,3,5-triazinan-2-ylidene)-N-1,3-thiazol-2-amines was obtained as a result of the multicomponent condensation of methyl (2Z)-[2[(diaminomethylene)amino]-4-oxothiazol-5(4H)-ylidene]acetate with alkylamines and formaldehyde. [ABSTRACT FROM AUTHOR]

Novel preparative approach for the synthesis of alkylamines with 1,3,4-oxadiazole heterocyclic substituent is described. This method is based on unusual cascade transformation involving formal (4+1) cyclocondensation of hydrazides of amino acids with nitroalkanes electrophilically activated in the presence of polyphosphoric acid. [ABSTRACT FROM AUTHOR]

Transition‐metal‐catalyzed multicomponent carbonylation is one of the most efficient strategies to construct carbonyl‐containing compounds. Herein, a palladium‐catalyzed four‐component perfluoroalkylation/aminocarbonylation of unactivated alkenes with perfluoroalkyl halides, and amines was developed. A wide range of substrates, including anilines, alkylamines, sulfonamides, and hydrazines are all suitable reaction partners for this catalyst system, resulting in various β‐perfluoroalkyl amides with good functional‐group tolerance and excellent chemoselectivity. Furthermore, not only alkyl olefins, but also aliphatic alkynes, and even alkyl allenes can all be employed. Notably, several medical and bioactive related molecules are compatible here as well. [ABSTRACT FROM AUTHOR]

The name of Menshutkin is most frequently associated with his eponymous reaction (the quaternization of tertiary amines with alkyl halides). However, he made encyclopedic contributions to the field of reaction kinetics, where he carried out extensive studies of the effects of reactant structure on the rates of esterification of monohydric, dihydric and trihydric alcohols with monocarboxylic acids, and monobasic and dibasic carboxylic acids and anhydrides with monohydric alcohols. In these studies, he deduced an order of reactivity of alcohols in esterification on the basis of their reactions with acetic acid, and the effects of acid structure on the rates of esterification based on the reaction of the carboxylic acid with isobutyl alcohol. When his attention later turned to the substitution chemistry of amines, he defined the parameters that affected their reactions: anilines were less reactive than alkylamines, secondary more reactive than primary amines, and the reaction was accelerated by replacing benzene as a solvent with alcohols. The wide‐ranging work of Menshutkin, the physical organic chemist, is discussed. [ABSTRACT FROM AUTHOR]

The molecular sieve HZSM-5A was modified by incorporation of two alkylamines (C8H17-CH = NH, C10H21-CH = NH; loading materials) and such two surfactant modified zeolites (SMZs), SMZ-C8 and SMZ-C10, were served as the active substance in lead ion-selective electrode (ISE). Optimization of the polyvinyl chloride (PVC)-based membrane electrodes was obtained for a membrane composition of 30% PVC, 65% dioctyl phthalate (DOP) and 5% (w/w) carrier. The ISEs exhibited Nernstian slopes of 25.9 ± 0.3 and 28.6 ± 0.3 mV/decade for Pb2+ with the detection limits of 5.89 (± 0.12) × 10–7 M and 6.08 (± 0.16) × 10–9 M in the concentration of 1.0 × 10–2 to 1.0 × 10–6 M and 1.0 × 10–3 to 1.0 × 10–8 M, respectively. The lifetime of the electrodes was found at least 8 weeks and their response time was less than 10 s. The ISEs did not suffer interference from most metal cations and were successfully used as indicator electrodes for potentiometric titration of Pb2+ with K2CrO4 and for determinations of Pb2+ in an alcoholic beverage and tea leaves samples. [ABSTRACT FROM AUTHOR]

Regio‐ and enantioselective hydroarylamination, hydroalkylamination and hydroamidation of styrenes have been developed by NiH catalysis with a simple bioxazoline ligand under mild conditions. A wide range of enantioenriched benzylic arylamines, alkylamines and amides can be easily accessed by nitroarenes, hydroxylamines and dioxazolones, respectively as amination reagents. The chiral induction in these reactions is proposed to proceed through an enantiodifferentiating syn‐hydronickellation step. [ABSTRACT FROM AUTHOR]