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Hydrogen transfer reactions from tertiary amines to phenyl- and alkyl-substituted alkynes catalyzed by Pt and Pd supported on carbon are investigated. Evidence of a sequential two-cycle mechanism s...

Introduction of alkyl groups on azodicarboxylate esters is an important method to prepare alkyl amine derivatives. Herein, we report reactions of 4-alkyl-1,4-dihydropyridines as alkylation reagents with di- tert-butyl azodicarboxylate to prepare alkyl amine derivatives under heating conditions. The alkylation reactions via C-C bond cleavage of the dihydropyridines are achieved in the absence of catalysts and additives.

Intramolecular imino-ene reaction of 2 H-aziridine has been studied experimentally and computationally, demonstrating that (1) the concerted process takes place regioselectively on the alkene E-CH group; (2) the geometry of the N-linker impacts the reaction activation energy and diastereoselectivity significantly, with pyramidal alkyl amine as the linkage, an exclusive cis-product is achieved; (3) when the reaction has to occur with the Z-CH group, the cis-diastereoselectivity is solely observed regardless of the nature of the N-linkage.

A Negishi cross-coupling of alkyl pyridinium salts and alkylzinc halides has been developed. This is the first example of alkyl–alkyl bond formation via cross-coupling of an alkyl amine derivative with an unactivated alkyl group, and allows both primary and secondary alkyl pyridinium salts to react with primary alkylzinc halides with high functional group tolerance. When combined with formation of the pyridinium salts from primary amines, this method enables the non-canonical transformation of NH(2) groups into a wide range of alkyl substituents with broad functional group tolerance.

Glyphosate is the highest-selling pesticide in Brazil. It is one of the most-seized pesticides by the Brazilian Federal Police. However, smuggled agrochemicals show characteristics unknown from chemical, physical, and biological viewpoints, which should be determined. Quantitative nuclear magnetic resonance (qNMR) spectroscopy is a simple, rapid, and non-destructive methodology that allows simultaneous qualification and quantification of various substances (target and non-target). We developed and validated a method for quantification of the target (glyphosate) in commercial and smuggled products, and qualified the not-target contaminants. Validation was undertaken according to regulation ABNT NBR 14029: 2016 and Association of Analytical Communities criteria. Samples were diluted in D2O and analysed NMR. The method was applied to analyses of 10 glyphosate-based samples: eight commercial and two illegal. All commercial samples demonstrated the percentage of active principle specified by the manufacturer. However, the illegal GLIFP02 sample had a concentration of 33.57% over the reported content. GLIFP01 did not show any formulation description on the label, and showed only 6.10% of active principle in relation to GLIFP02. Also, it was possible to detect polyethoxylated alkyl amine (POEA) in legal and illegal samples. POAE has proven toxicity. Principal component analysis was used to demonstrate that the qNMR method could differentiate between samples of these pesticides. This was the first work to report application of qNMR spectroscopy, an easy, rapid, and non-destructive method, for qualification and quantification of target and not-target compounds in pesticide samples based on glyphosate.

Chiral alkyl amines are omnipresent as bioactive molecules and synthetic intermediates. The catalytic and enantioselective synthesis of alkyl amines from readily accessible precursors is challenging. Here we develop a nickel-catalyzed hydroalkylation method to assemble a wide range of chiral alkyl amines from enecarbamates (N-Cbz-protected enamines) and alkyl halides with high regio- and enantioselectivity. The method works for both nonactivated and activated alkyl halides and is able to produce enantiomerically enriched amines with two minimally differentiated α-alkyl substituents. The mild conditions lead to high functional group tolerance, which is demonstrated in the postproduct functionalization of many natural products and drug molecules, as well as the synthesis of chiral building blocks and key intermediates to bioactive compounds.

High-efficiency absorbent is a prerequisite for CO2 capture from the atmosphere to alleviate environmental degradation. Herein, grand canonical Monte Carlo (GCMC) was used to investigate the CO2 adsorption and separation behaviors in four alkyl anime functionalized triphenylamine-based covalent organic frameworks (TPA-xC-NH2, x = 1–4). Results show that a longer alkyl anime chain has a more remarkable effect on the CO2 adsorption capacity and separation over N2. The alkyl amine chain owning four carbon atoms of TPA-4C-NH2 exhibits the best performance. The CO2 adsorption capacity in TPA-4C-NH2 is 3.41 mmol/g at 298 K and 5.26 mmol/g at 273 K and 1 bar, thereby enhancing the CO2 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.

The ruthenium(II)-catalyzed C-H aminocarbonylation of N-(hetero)aryl-7-azaindoles with isocyanates is described. The excellent site selectivity at the ortho-position within the N-(hetero)aryl ring was observed to provide ortho-amidated N-(hetero)aryl-7-azaindoles under the mild reaction conditions. The resulting 7-azaindole derivatives can be readily transformed into 7-azaindoles containing carboxylic acid and alkyl amine functional groups.

We have studied Pt surfaces for which activity towards the oxygen reduction reaction (ORR) is enhanced by adsorbed amines: octylamine (OA) and an alkyl amine containing a pyrene ring (PA). Adsorbed OA/PA (molar ratio 9/1) enhances activity for ORR on n(111)–(111) surfaces of Pt for terrace atomic rows n greater than 7. The activity on Pt(111), the surface of which is a flat terrace, is particularly enhanced. On Pt(100), which also has a flat terrace, however, the ORR activity is greatly reduced. It is shown that adsorbed OA/PA enhances the ORR on surfaces with a wide (111) terrace, but deactivates the ORR on the (100) terrace. Keywords: Enhancement of oxygen reduction reaction, Single crystal electrodes of Pt, Alkylamine, Wide (111) terrace

The design and synthesis of flexible monomer-based covalent organic frameworks (COFs) have been considered a challenge. Herein, we describe the design and synthesis of a new flexible monomer-based COF, termed PPN-30 (PPN meaning porous polymer network), by the use of a flexible alkyl amine, 1,4-cyclohexanediamine, combined with 1,3,5-triformylbenzene. The structure and gas adsorption properties of PPN-30 were carefully investigated.

The present study aimed at screening conglomerate derivatives of racemic chlocyphos (4-(2-chlorophenyl)-5,5-dimethyl-2-hydroxy-1,3,2-dioxaphosphorinane 2-oxide) and to perform enantiomeric separati...

CO2 emulsion/foam is a promising method for controlling the mobility and improving the volumetric sweep efficiency in CO2 enhanced oil recovery (CO2-EOR) process. Recently, amine surfactants attract the attention of the researchers as CO2 emulsifiers/foamers, because of their switchable property: the surfactants are nonionic and CO2 soluble at high pH, and are cationic and water soluble at low pH. However, the efficiency of the commercial switchable amine surfactants is usually suppressed at high salinity (> 200 g/L TDS) and temperature (> 100 °C). Thus, novel switchable alkyl-amine surfactants are designed in house based on the hydrophilic and CO2-philic balance for rapidly generating strong and stable CO2 emulsions at high salinity and high temperature. These novel surfactants are evaluated and compared to a commercial one with respect to the solubility in brine and CO2, and emulsifying ability in bulk and in porous media at high temperature, high pressure and high salinity.The novel surfactants show outstanding performance: soluble in 220 g/L NaCl brine at pH≤8 from room temperature to 120 °C, soluble in CO2 at relatively low pressure (91 bar) and high temperature (110 °C). The surfactants are thermally stable at 110 °C and pH=4 in the absence of O2. Strong CO2 emulsion/foam is observed in both bulk test and in silica sandpack with 0.2 (wt)% of the surfactant in brine. Additionally, the apparent viscosity of the CO2 emulsion/foam at 110 °C is significantly higher than that at lower temperatures. Comparing to the commercial surfactants, the CO2 emulsion/foam is stronger and generated faster by the novel surfactants. These novel surfactants can be synthesized using commercially available feeds and simple industrial processes. Thus, the novel surfactants are promising for generating the CO2 emulsion/foam, especially in the hot and salty carbonate reservoirs.

The direct alcohol amination constitutes an attractive process for N-alkyl amine synthesis because alcohol is readily available, and water is generated as the sole by-product. In the last century, the coupling of amines with alcohols has been extensively studied and positive results were obtained. In this chapter, the development of alcohol amination is summarized. The typical results with homogeneous and heterogeneous catalyst systems based on noble metals, nonnoble metals, and transition-metal free and acid catalysts are described.

We report a chemiresistive sensor approach based on a TTF–TCNQ charge transfer material, which can real-time detect and distinguish the vapors of alkyl amine and aromatic amine species under ambient conditions, based on the dramatic difference in the kinetics of the electric current recovery processes after the exposure of the two amine species.

Various glucosylamines were synthesized from glucose and different alkyl amine compounds. These amino compounds are β- d -glucopyranosylamine (GPA), N -ethyl-β- d -glucopyranosylamine (EtGPA), N -butyl-β- d -glucopyranosylamine (BuGPA), N -hexyl-β- d -glucopyranosylamine (HeGPA), N -octyl-β- d -glucopyranosylamine (OcGPA), N -dodecyl-β- d -glucopyranosylamine (DoGPA), N -(2-hydroxyethyl)-β- d -glucopyranosylamine (HEtGPA) and N , N -di(2-hydroxyethyl)-β- d -glucopyranosylamine (DHEtGPA). They were tested for their antifungal activity against the growth of Coriolus versicolor and Poria placenta . An improvement of the antifungal activity with the increase of alkyl chain length was observed. DoGPA exhibited the best antifungal activity against both strains. It completely inhibited the fungal growth at 0.01 × 10 −3 mol mL −1 and 0.0075 × 10 −3 mol mL −1 for C. versicolor and P. placenta , respectively. For other glucosylamines higher concentrations were needed for complete inhibition of fungi.