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Understanding how hydrotreating oxygen-containing compounds together with nitrogen-containing compounds affects the reactivity and selectivity is relevant for processing renewable feedstocks. In this work, competitive hydrodeoxygenation (HDO) and hydrodenitrogenation (HDN) reactions were studied by co-hydrotreating palmitic acid (C16 acid) and tetradecylamine (C14 amine) over a Pt/ZrO2 catalyst in a batch reactor. HDO proceeded faster than HDN in the studied system, and the deoxygenation reactions were found to have an inhibitory effect on HDN. Co-hydrotreating the C16 acid and the C14 amine expanded the reaction network from the individual HDO and HDN networks and changed the prevailing reaction pathways, initially in favor of oxygen removal. The formation of heavy secondary amides and amines through condensation reactions became increasingly favored as the share of C16 acid in the feed increased. For a given conversion level, the condensation product selectivity was observed to increase as the reaction temperature was decreased, whereas increasing the reaction temperature promoted the formation of the desired paraffins. This work described the ease of HDO compared to HDN, the role of condensation reactions in the co-hydrotreating reaction network, and the inhibitory effect on HDN thereof. [ABSTRACT FROM AUTHOR]

[Display omitted] • MIL-101 s with 6 functional groups (FGs: like alkyl and aryl –NH 2) were prepared. • MIL-101 s with 6 FGs (in similar molar conc.) were compared in CO 2 adsorption. • The performance of FGs is in the order: alkyl –NH 2 > -SO 3 H>-aryl –NH 2 > –NO 2. • This hierarchy can be supported by different adsorption mechanisms because of FGs. • In CO 2 adsorption, aryl amines should be differentiated from alkyl amines. In this study, we investigated the effect of functional groups of metal–organic frameworks (MOFs) on CO 2 adsorption at low pressure through experimental and computational approaches. We compared the performance of −SO 3 H, –NO 2 , aryl –NH 2 , and alkyl –NH 2 groups (in similar molar quantities) in CO 2 adsorption under the same conditions. The adsorption efficiency followed in the order: alkyl –NH 2 > -SO 3 H>aryl –NH 2 > –NO 2 because of the different adsorption mechanisms over the groups. The main mechanism over alkyl –NH 2 was the formation of ammonium carbamate via the carbamic acid formation. The adsorption mechanism over −SO 3 H and aryl –NH 2 groups was Lewis acid-base and H-bonding interactions, while that over –NO 2 group was solely Lewis acid-base interaction. The alkyl amine exhibited the best performance (in adsorption capacity, selectivity, and adsorption heat) due to its ability to form carbamate readily. On the contrary, aryl amine demonstrated lower performance than −SO 3 H groups, attributed to their low capability to form carbamate. These findings underscore the importance of amine type in CO 2 adsorption, highlighting that aryl amines, different from alkyl amines, perform worse than other functional groups, such as −SO 3 H. [ABSTRACT FROM AUTHOR]

Azetidines are an important type of saturated, highly strained, four-membered, nitrogen-containing heterocyclic compound. These compounds serve as important raw materials, intermediates, and catalysts in organic synthesis, as well as important active units in amino acids, alkaloids, and pharmaceutically active compounds. Thus, the development of an efficient and concise method to construct azetidines is of great significance in multiple disciplines. In this work, we reported on the photo-induced copper-catalyzed radical annulation of aliphatic amines with alkynes to produce azetidines. This reaction occurred in a two- or three-component manner. The alkynes efficiently captured photogenerated α-aminoalkyl radicals, forming vinyl radicals, which initiated tandem 1,5-hydrogen atom transfer and 4-exo-trig cyclization. Density functional theory calculations indicated that the tertiary radical intermediate was critical for the success of cyclization. In addition, the resulting saturated azetidine scaffolds possessed vicinal tertiary-quaternary and even quaternary-quaternary centers.

Highlights • Small alkyl amines are ideal for ion pair HPLC of phosphate diester oligonucleotides. • Resolution of positional isomers of impurities can be achieved. • Addition of long chain alkyl acids further improves resolution. • Desulfurization permits extension to phosphorothioate oligonucleotides. Abstract In an effort to improve separation of impurities in oligonucleotide drugs, alkyl amines of different length and carbon content were evaluated as reagents in ion pair-reversed phase (IP-RP) HPLC with mass spectrometric detection. A range of columns was tested in combination with different buffers, ion-pair modifiers and varying pH adjustments. For phosphorothioate oligonucleotides, larger amines, like tributyl and hexyl amine provided the best chromatography, as small amines tended to broaden peaks due to the separation of diastereoisomers. For phosphate diester oligonucleotides, the best separations were obtained using small alkyl amines, like propyl-, isopropyl- and diethylamine. Conditions optimized for oligonucleotide sequence and type of impurity enabled full separation of the individual components of composite impurities, such as n-1, N 3-(2-cyanoethyl)thymine (CNET), deaminated and 3-(2-oxopropyl)imidazopyrimidinone (OPC) impurities. The addition of long-chain alkyl acids like hexanoic acid to the IP buffer resulted in further improvements in peak separation. [ABSTRACT FROM AUTHOR]

High-efficiency absorbent is a prerequisite for CO 2 capture from the atmosphere to alleviate environmental degradation. Herein, grand canonical Monte Carlo (GCMC) was used to investigate the CO 2 adsorption and separation behaviors in four alkyl anime functionalized triphenylamine-based covalent organic frameworks (TPA-xC-NH 2 , x = 1–4). Results show that a longer alkyl anime chain has a more remarkable effect on the CO 2 adsorption capacity and separation over N 2 . The alkyl amine chain owning four carbon atoms of TPA-4C-NH 2 exhibits the best performance. The CO 2 adsorption capacity in TPA-4C-NH 2 is 3.41 mmol/g at 298 K and 5.26 mmol/g at 273 K and 1 bar, thereby enhancing the CO 2 adsorption capacity by 50.2% and 30.5%, respectively, with a 121% selectivity increase compared with that of the pristine TPA-COF. The pore characteristic, isosteric heat, coulomb/non-coulomb interaction, and selectivity are analyzed to elucidate the enhancement mechanisms. [ABSTRACT FROM AUTHOR]

ABSTRACT The aliphatic polyurethane with pendant alkyne, perfluorophenyl, and anthracene moieties (PU-anthracene) was prepared from polycondensation of anthracene, alkyne, and perfluorophenyl functional-diols with hexamethylenediisocyanate in the presence of dibutyltindilaurate (DBTL) in CH2Cl2 at room temperature for 10 days. Thereafter, the PU-(anthracene- co-alkyne- co-perfluorophenyl) ( Mn,GPC = 15,400 g/mol, Mw/ Mn= 1.37, relative to PS standards) was sequentially clicked with benzyl azide, octylamine, and 4-(2-hydroxyethyl)−10-oxa-4-azatricyclo[5.2.1.02,6]dec-8-ene-3,5-dione (adduct alcohol) via copper-catalyzed azide-alkyne cycloaddition, active ester substitution and Diels-Alder reactions, respectively, to finally yield PU-(hydroxyl- co-benzyltriazole- co-octylamine). The PUs were characterized using 1H NMR, GPC, and DSC. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016, 54, 480-486 [ABSTRACT FROM AUTHOR]

The article discusses pyrroloquinoline quinone-dependent quinoprotein alcohol dehydrogenases (PQQ-ADH) from pseudomonas putida KT2440 (P/rADH) which was activated by several primary amines including di-methylamine, and tri-methylamine. Topics discussed include pentylamine as an activator, stimulatory and inhibitory activator-binding sites of M. methylotrophus, and assays of the catalytic activity.

Abstract: A four-component reaction between 2-formylbenzoic acid, malononitrile, isocyanides, and primary alkyl amines has been developed for an efficient preparation of 2-(1-(alkylcarbamoyl)-2,2-dicyanoethyl)-N-alkylbenzamide and 1,7-diazaspiro[4,4]nonane-2,6-dione derivatives under two different conditions. It is shown that simply by changing the reaction solvent from ethanol to dichloromethane and controlling the order of the addition of reagents, two completely different products can be obtained. These multicomponent reactions showed high atom economy. [Copyright &y& Elsevier]

Color filters (CFs) are important elements for making color images in liquid crystal displays (LCDs) and other imaging devices. A colored layer is fabricated with colorants of red, green, and blue from either dyes or pigments. These colorants are arranged uniformly and make up the CF while also converting white backlight into a color image. The pigment is advanced to thermal stability, light resistance and chemical resistance, so many used for manufacturing color filters. However, the color filters manufactured with pigments have spectral drawbacks such as decreased transmittance of light and decreased contrast ratio both caused by aggregation of pigment particles. Thus, it is necessary to do the expensive and time-consuming dispersion process for obtaining stable and finer pigment millbases without molecular aggregation. In this study, our focus was on a new series of acid dye systems that have alkyl amine groups because it has an advantage in solubility of organic solvents. As a result of our focus, we have designed and synthesized new acid dyes that consist of alkyl amine groups, using a simple method of reaction. In addition, manufacturing color filters without the milling process in the optical characteristics, thermal, chemical stability were investigated. [ABSTRACT FROM PUBLISHER]

Highlights: [•] Cationic collectors adsorb on the surface through electrostatic interactions. [•] The MD results reproduce the hydration energies of water molecules on muscovite (001) surface. [•] Ammonium ions have thermodynamic advantages to resist the hydration layer. [ABSTRACT FROM AUTHOR]

Novel ammonium surfactant salts based on alkyl iodides and alkyl amine are synthesised. Their surface activity is determined by stalagmometric measurements. Petroleum collecting and dispersing properties of these surfactants are studied under laboratory conditions. The tests are carried out in four types of water. The results of these experiments confirm the very important role of salinity of water for exhibition of petroleum collecting or dispersing capacity of surfactants. Studies on various kinds of crude oils show that with the decrease in their viscosity, the efficiency of the surfactants increases. Complexes of ammonium salts with acrylate co-polymer are obtained. The petroleum collecting and dispersing properties of these complexes are also investigated. The polymeric complexes do not concede by efficiency to the surfactant salts in some cases surpassing them. [ABSTRACT FROM AUTHOR]

Abstract: Pendant drop and buoyant bubble methods have been used to study the surface characteristics of alkyl amines at the water/air surface. The investigated alkyl amines, triethylamine and octylamine, showed unusual changes in the surface tension as a function of time: an initially steep drop and a subsequent steady increase in the surface tension until a value close to the one of the pure water/air system was observed. This phenomenon is explained by the evaporation of the alkyl amines, for which several sets of experiments have been conducted with the pendant drop and buoyant bubble methods. Using an appropriate experimental protocol, the equilibrium adsorption behaviour of the two amines can be quantitatively measured. [Copyright &y& Elsevier]

Abstract: Densities, ρ, viscosities, η, and speeds of sound, u, were measured for the binary liquid mixtures containing diethylenetriamine with 2-methyl-1-propanol, 2-propanol and 1-butanol at 293.15, 298.15, 303.15, 308.15 and 313.15K. From density and speed of sound data, excess molar volumes, and deviations in isentropic compressibility, Δκ s , and speed of sound, Δu have been evaluated. Viscosity data were used to compute deviations in viscosity and excess Gibbs energy of activation of viscous flow ΔG* E at 298.15, 303.15 and 308.15K. A Redlich–Kister type equation was applied to fit the excess molar volumes and deviations in isentropic compressibility, speed of sound and viscosity data. The viscosity data have been correlated with the equations of Grunberg–Nissan, Tamura–Kurata, Heric–Brewer and of Hind et al. All the binary systems of the present study have negative values of excess molar volumes and deviations in isentropic compressibility over whole composition range and at all temperatures which indicates strong interactions between the components of binary mixtures. [Copyright &y& Elsevier]

Abstract: The sigma1 receptor is distinguished for its ability to bind various pharmacological agents including drugs of abuse such as cocaine and methamphetamine. Some endogenous ligands have been identified as putative sigma1 receptor regulators. High affinity ligands for the sigma1 receptor contain a nitrogen atom connected to long alkyl chains. We found that long alkyl chain primary amines including endogenous amines belonging to the sphingolipid family such as d-erythro-sphingosine and sphinganine bind with considerable affinity to the sigma1 receptor but not to the sigma2 receptor. The binding of d-erythro-sphingosine to the sigma1 receptor appears to be competitive in nature as assessed against the radioligand [3H]-(+)-pentazocine. Interestingly, the well studied sphingolipid mediator sphingosine-1 phosphate did not bind to the sigma1 or the sigma2 receptor. Sphingosine is converted to sphingosine-1 phosphate by a family of sphingosine kinases that regulate the relative levels of these two bioactive lipids in the cell. The selective binding of sphingosine but not sphingosine-1 phosphate to the sigma1 receptor suggests a mechanism for regulation of sigma1 receptor activity by the sphingosine kinase. We have successfully reconstituted this hypothetical model in HEK-293 cells overexpressing both the sigma1 receptor and sphingosine kinase-1. The data presented here strongly supports sphingosine as an endogenous modulator of the sigma1 receptor. [Copyright &y& Elsevier]

Abstract: The solid–vapor reaction properties of three transition metal sulfonates and amines were investigated and the reaction products were characterized by EA, TGA, IR, PXRD and single crystal structure analyses. [Cu(1,5-nds)(H2O)4] n (I), [Cu(H2O)6](1,5-nds) (II) (1,5-nds=1,5-naphthalenedisulfonate) and [Cd(p-NH2C6H4SO3)2] (III) can react with primary alkyl amine vapors and form stable monoamine-coordinated Cu(II) and Cd(II) complexes. All of the amine adducts are crystalline materials. The reactions between [Cd(p-NH2C6H4SO3)2] (III) and C2H5NH2 or n-C3H7NH2 produced single crystals in situ via the solid–vapor reaction process. [Copyright &y& Elsevier]

e. bore and s. langsrud. 2004.To characterize micro-organisms isolated from Norwegian dairy production plants after cleaning and fogging disinfection with alkyl amine/peracetic acid and to indicate reasons for survival.Microbial samples were collected from five dairy plants after cleaning and fogging disinfection. Isolates from two of these production plants, which used fogging with alkylamino acetate (plant A), and peracetic acid (plant B), were chosen for further characterization. The sequence of the 16S ribosomal DNA, fatty acid analysis and biochemical characteristics were used to identify isolates. Three isolates identified asRhodococcus erythropolis,Methylobacterium rhodesianumandRhodotorula mucilaginosawere isolated from plant A and oneSphingomonassp. and twoM. extorquensfrom plant B. Different patterns of resistance to seven disinfectants in a bactericidal suspension test and variable degree of attachment to stainless steel were found. The strains with higher disinfectant resistance showed lower degree of attachment than susceptible strains.The study identifies and characterizes micro-organisms present after cleaning and fogging disinfection. Both surface attachment and resistance were shown as possible reasons for the presence of the isolates after cleaning and disinfection.These results contribute to the awareness of disinfectant resistance as well as attachment as mechanisms of survival in dairy industry. It also strengthens the argument of frequent alternation of disinfectants in the food processing industry to avoid the establishment of resistant house strains. [ABSTRACT FROM AUTHOR]

Azetidines are an important type of saturated, highly strained, four-membered, nitrogen-containing heterocyclic compound. These compounds serve as important raw materials, intermediates, and catalysts in organic synthesis, as well as important active units in amino acids, alkaloids, and pharmaceutically active compounds. Thus, the development of an efficient and concise method to construct azetidines is of great significance in multiple disciplines. In this work, we reported on the photo-induced copper-catalyzed radical annulation of aliphatic amines with alkynes to produce azetidines. This reaction occurred in a two- or three-component manner. The alkynes efficiently captured photogenerated α-aminoalkyl radicals, forming vinyl radicals, which initiated tandem 1,5-hydrogen atom transfer and 4- exo -trig cyclization. Density functional theory calculations indicated that the tertiary radical intermediate was critical for the success of cyclization. In addition, the resulting saturated azetidine scaffolds possessed vicinal tertiary-quaternary and even quaternary-quaternary centers., Competing Interests: The authors declare no competing financial interests., (© 2022 The Author(s).)

• Small alkyl amines enhance ion pair HPLC of phosphate diester oligonucleotides. • Differentiation of individual members of composite impurity families can be achieved. • Addition of alkyl acids further enhances peak separation. • Lower amounts of ion pair reagents increase sensitivity of detection. • Increased sensitivity allows for tandem MS determination of co-eluting impurities. Ion pair-reversed phase (IP-RP) HPLC is one of the most widely used methods for the analysis of oligonucleotide impurities. The method is compatible with mass spectrometry and has been used to guide the development of improved synthesis and purification approaches. The ability to detect and characterize impurities depends on the reagents and the IP buffer system employed, as each can directly affect the degree of chromatographic separation and the sensitivity of detection by MS. Previous work in our laboratory has shown that small alkyl amines are suitable IP reagents for the analysis of impurities in phosphate diester oligonucleotides and can be used to differentiate among individual members of composite impurity families. The addition of an alkyl acid often further enhances peak separation, but at the detriment of ion signal. An improved method with increased chromatographic performance and sensitivity of detection is presented here. Improvements were mainly realized through the use of lower concentrations of small alkyl amine (i.e., 5 mM) and acid (0.5 mM) IP reagents, and ammonium bicarbonate (20 mM) as a buffer. The improved capabilities of the new method are demonstrated by separation of the individual components of the composite n − 1 impurity in a set of four production-scale batches of a single oligonucleotide. Addition of the alkyl acid resulted in resolution of most individual n − 1 impurities. The observed enhanced sensitivity of detection allowed multiple reaction monitoring (MRM) experiments, which were used to differentiate among unresolved impurities. [ABSTRACT FROM AUTHOR]