Alkyl Amides Research Articles

Safety Assessment of Alkyl Amide MIPA Ingredients as Used in Cosmetics.

The Expert Panel for Cosmetic Ingredient Safety (Panel) assessed the safety of 14 alkyl amide MIPA ingredients as used in cosmetics. All of these ingredients are reported to function in cosmetics as a surfactant - foam booster and/or viscosity increasing agent. The Panel considered the available data, as well as data on read-across sources, and concluded these ingredients are safe in cosmetics in the present practices of use and concentration described in this safety assessment when formulated to be non-irritating.

Merging Boryl Radical-Mediated Halogen-Atom Transfer and Copper Catalysis for the Alkylation of Amides

Merging Boryl Radical-Mediated Halogen-Atom Transfer and Copper Catalysis for the Alkylation of Amides

In-situ halloysite functionalization of anionic hybrid gels possessing easily implemented site-specific (alkyl)amide and carboxyl groups

Design of functional materials with tunable properties based on anionically-modified copolymer network of poly (N-isopropyl acrylamide-co-methacrylic acid) P(NIPA-co-MA) containing linear polyacrylamide and various amounts of Halloysite nanotubes (Hal) was presented using a facile route of solution casting. The organic/inorganic nanostructures based on thermo-responsive PNIPA were constructed to create hybrid materials via in situ polymerization with different Hal-loading and then used for the removal of cationic methylene blue (MB) dye from aqueous solutions. To achieve the desired mechanical property, the optimum composition of hybrids was determined following a simple and cost-effective synthesis procedure. In situ one-pot polymerization was promoted by semi-IPN formation, following a much simpler route than traditional preparation approaches for stable cross-linked hybrid formation. The swelling of hybrids decreased by 2.9-fold with loading of 5.40 % Hal, confirming the hydrogen bonding interactions between Hal and PAAm/P(NIPA-co-MA) network. The mechanical properties of Hal-doped hybrid gels showed an increase–decrease tendency with increase of Hal-content from 0.80 to 5.40 % (w/v) due to the high aspect ratio of Hal and strong secondary interactions between Hal and PAAm/P(NIPA-co-MA) chains. The effective cross-link density for Hal-doped hybrids was expressed by a cubic polynomial as a function of Hal concentration. Temperature-sensitive swelling results showed that the advantage of sustained release property of Hal can be combined with excellent controllability of PNIPA-based network. Adsorption results of MB onto Hal-doped hybrids bearing methacrylic acid moieties demonstrated their potential as efficient adsorbents for the removal of cationic dyes. A new route offered by the proposed procedure for design of hybrids containing “green” one-dimensional nanofillers creates an innovative perspective on robust hybrid structures for practical applications.

Sustainable lignin-based powder coatings doped with ZnO displayed excellent UV resistance properties

Lignin with increased polyhydroxyl content (LOH) was prepared via a one-pot synthesis using enzymatically hydrolyzed lignin (EHL) as the raw material. The modified structure and hydroxyl content of LOH were analyzed using FT-IR, 1H NMR, and 31P NMR. LOH was blended with zinc oxide (ZnO), polyester resin and hydroxyl alkyl amide (HAA) to prepare polyester powder coatings. The anti-UV properties of the coating were significantly enhanced by the addition of LOH and ZnO. The coating exhibits exceptional adhesion, rating at level 0, and achieves a pencil hardness of 7H. The gel time for the coating is 195 s, and it has a 5-degree Celsius increase in melting temperature, which greatly enhances its storage stability. Considering a range of factors, the formula LOH7.5 % has been identified as the optimal composition. The results of this study demonstrate an easy approach to developing sustainable lignin-based powder coatings with excellent properties.

A Radical Strategy for the Alkylation of Amides with Alkyl Halides by Merging Boryl Radical-Mediated Halogen-Atom Transfer and Copper Catalysis.

Amide alkylation is a fundamental process in organic chemistry. However, the low nucleophilicity of amides means that divergent coupling with alkyl electrophiles is often not achievable. To circumvent this reactivity challenge, individual amine synthesis followed by amidation with standard coupling agents is generally required. Herein, we demonstrate a radical solution to this challenge by using an amine-borane complex and copper catalysis under oxidative conditions. While borohydride reagents are generally used as reducing agents in ionic chemistry, their conversion into amine-ligated boryl radicals diverts their reactivity toward halogen-atom transfer. This enables the conversion of alkyl halides into the corresponding alkyl radicals for amide functionalization via copper catalysis. The process is applicable to the N-alkylation of primary amides employing unactivated alkyl iodides and bromides, and it was also showcased in the late-state functionalization of both complex amide- and halide-containing drugs.

Gas channeling control with CO2-responsive gel system in fractured low-permeability reservoirs: Enhancing oil recovery during CO2 flooding

During the CO2 flooding process in fractured low-permeability oil reservoirs, the injected CO2 is prone to channeling along fractures due to severe reservoir heterogeneity, resulting in poor development effect. The CO2-responsive gel system shows dual advantages in achieving CO2 capture and plugging gas channeling to enhance oil recovery. This paper constructed a system with good CO2 sensitivity based on long-chain alkyl amide propyl dimethyl tertiary amine first. Subsequently, the properties of the system before and after the response were evaluated through rheological test, and its microstructure was characterized by Cryo-TEM. The system exhibited good CO2 responsiveness, transitioning from low-viscosity solution system to high-viscosity CO2-responsive gel system upon contact with CO2, with its viscosity increasing by nearly five orders of magnitude. The CO2-responsive gel demonstrated excellent shear resistance, viscoelasticity and shear self-repairing ability. The change of microstructure further verified the mechanism of molecules self-assembly in the system under the action of CO2. Then, a series of core physical simulation experiments were carried out to comprehensively evaluate the effects of different factors on the injection capacity, plugging characteristics, dynamic filtration damage performance and EOR effect of CO2-responsive gel. The gel maintained injectability while achieving an exceptional deep plugging effect, and the plugging rate reached 98.77%. It showed good characteristics of low filtration and permeability damage in low permeability reservoirs, effectively ensuring the fracture plugging effect. After the fracture was plugged by gel, the sweep range of CO2 to the matrix significantly expanded, and the gas flooding recovery increased by 18.19–21.7%. Finally, the matrix-fracture dual-media chip model was used to conduct microfluidic experiment, the oil displacement characteristics in different displacement stages were visually clarified, and the synergistic plugging and oil displacement mechanism between the CO2-responsive gel and CO2 was summarized. The research results can provide important insights for the green and efficient application of CO2-responsive gel in fractured low-permeability reservoirs.

The discovery of indazapyroxamet: a novel 3-pyridinyl insecticide targeting piercing/sucking insectsa.

In recent years, the registrations for a number of commercial insecticides utilized for piercing/sucking insects have been cancelled or restricted. To meet this growing need for new hemipteran controlling agrochemicals, we discovered a 2-(pyridin-3-yl)-thiazole compound, with limited insecticidal activity against cotton/melon aphid (Aphis gossypii). The 2-(pyridin-3-yl)-thiazole moiety offered us a basis to pursue the bicyclic 2-(pyridin-3-yl)-2H-indazole carboxamides. Evaluation of such 2-(pyridin-3-yl)-2H-indazole carboxamides revealed that even analogs containing only simple alkyl amides attached at the 4 or 5 positions possess promising insecticidal activity. Extensive optimization of this novel class of 2-(pyridin-3-yl)-2H-indazole carboxamides led to identifying indazapyroxamet for commercial development. © 2024 Society of Chemical Industry.

Unveiling the Molecular Characteristics, Origins, and Formation Mechanism of Reduced Nitrogen Organic Compounds in the Urban Atmosphere of Shanghai Using a Versatile Aerosol Concentration Enrichment System.

Reduced nitrogen-containing organic compounds (NOCs) in aerosols play a crucial role in altering their light-absorption properties, thereby impacting regional haze and climate. Due to the low concentration levels of individual NOCs in the air, the utilization of accurate detection and quantification technologies becomes essential. For the first time, this study investigated the diurnal variation, chemical characteristics, and potential formation pathways of NOCs in urban ambient aerosols in Shanghai using a versatile aerosol concentration enrichment system (VACES) coupled with HPLC-Q-TOF-MS. The results showed that NOCs accounted over 60% of identified components of urban organic aerosols, with O/N < 3 compounds being the major contributors (>70%). The predominance of the positive ionization mode suggested the prevalence of reduced NOCs. Higher relative intensities and number fractions of NOCs were observed during nighttime, while CHO compounds showed an opposite trend. Notably, a positive correlation between the intensity of NOCs and ammonium during the nighttime was observed, suggesting that the reaction of ammonium to form imines may be a potential pathway for the formation of reduced NOCs during the nighttime. Seven prevalent types of reduced NOCs in autumn and winter were identified and characterized by an enrichment of CH2 long-chain homologues. These NOCs included alkyl, cyclic, and aromatic amides in CHON compounds, as well as heterocyclic or cyclic amines and aniline homologue series in CHN compounds, which were associated with anthropogenic activities and may be capable of forming light-absorbing chromophores or posing harm to human health. The findings highlight the significant contributions of both primary emissions and ammonium chemistry, particularly amination processes, to the pollution of reduced NOCs in Shanghai's atmosphere.

Deoxygenative Nucleophilic Phosphonation and Electrophilic Alkylation of Secondary Amides: A Facile Access to Quaternary α-Aminophosphonates.

The widespread occurrence and synthetic accessibility of amides render them valuable precursors for the synthesis of diverse nitrogen-containing compounds. Herein, we present a metal-free and streamlined synthetic strategy for the synthesis of quaternary α-aminophosphonates. This approach involves sequential deoxygenative nucleophilic phosphonation and versatile electrophilic alkylation of secondary amides in a one-pot fashion. Notably, this method enables the direct bis-functionalization of secondary amides with both nucleophiles and electrophiles for the first time, with simple derivatization leading to valuable free α-aminophosphonates by hydrolysis. The protocol has the advantages of operational simplicity, broad functional-group compatibility, environmental friendliness, and scalability to multigram quantities.

Cobalt nanoparticle-catalysed N-alkylation of amides with alcohols.

A protocol for efficient N-alkylation of benzamides with alcohols in the presence of cobalt-nanocatalysts is described. Key to the success of this general methodology is the use of highly dispersed cobalt nanoparticles supported on carbon, which are obtained from the pyrolysis of cobalt(ii) acetate and o-phenylenediamine as a ligand at suitable temperatures. The catalytic material shows a broad substrate scope and good tolerance to functional groups. Apart from the synthesis of a variety of secondary amides (>45 products), the catalyst allows for the conversion of more challenging aliphatic alcohols and amides, including biobased and macromolecular amides. The practical applicability of the catalyst is underlined by the successful recycling and reusability.

Upcycling of Poly(lactic acid) Waste: A Valuable Strategy to Obtain Ionic Liquids.

With the aim to investigate new strategies for upcycling of plastic waste, we performed aminolysis of poly(lactic acid) (PLA), using N,N-dimethylethylenediamine (DMEDA), N,N-dimethylpropylenediamine (DMPDA), and 3-aminopropylimidazole (API) as nucleophiles. The N-substituted lactamides obtained were alkylated by using alkyl halides differing in alkyl chain length, obtaining organic salts that in most cases behaved as ionic liquids (ILs). Both aminolysis of PLA and alkylation of amides were carried out taking into consideration the basic principles of the holistic approach to green chemistry, applied at a laboratory scale, and carefully selecting the nature of the reaction solvent, temperature range, and amount of reagents. Organic salts obtained from the alkylation of N-substituted lactamides were investigated to determine their glass or solid-liquid transitions and their thermal stability. Furthermore, cytotoxicity toward normal lung fibroblasts was also assessed. Data collected show that the proposed strategy represents a valuable protocol to upcycle plastic waste, using it as starting material to obtain alternative solvents of potential industrial relevance.

Pd(II)-Catalyzed C(sp3)–H Activation/Spirocyclization of Alkyl Amides

Pd(II)-Catalyzed C(sp3)–H Activation/Spirocyclization of Alkyl Amides

Anionic-nonionic and nonionic mixed surfactant systems for oil displacement: Impact of ethoxylate chain lengths on the synergistic effect

Compound surfactant system has been extensively studied in enhanced oil recovery (EOR) as the synergistic effect of mixed surfactants can increase the density of surfactants distributed at the oil/water interface, enhancing the interfacial activity and decreasing the interfacial tension. The system can further increase the capillary number and enhance oil recovery for oil-wet reservoirs. Studying the interactions between surfactant molecules is of great significance to the enhancement of practical application performances. In this study, N, N-dihydroxyethyl alkyl amide (CDEA), and Alkylphenol polyoxyethylene carboxylate (APEC) with different EO numbers were mixed to prepare a binary compound oil displacement system. The influence of the EO number on the synergistic effect of the CDEA/APEC system and the EOR potential was measured by interfacial tension, nanomechanical tests and oil-displacement experiments. The results indicate a synergistic effect between CDEA and APEC due to the formation of hydrogen bonds between the hydroxyl groups of CDEA and the EO chains of APEC. An optimal synergistic effect in the system was obtained when the EO number was four. The CDEA/APEC-4 system exhibited an oil/water interfacial tension decrease to 10−2 mN/m at 75 °C and the oil recovery was 57.14 %, which was increased by 19.2 % compared to primary water flooding. However, a longer EO chain length weakened the interaction forces between CDEA and APEC, which diminished the synergistic effect of the system, leading to an increase of the interfacial tension. Due to the flexibility of the EO chain, the increase in the EO number leads to the bending of APEC molecules. The longer EO chain length weakened the interaction forces between CDEA and APEC, which diminished the synergistic effect of the system, leading to an increase of the interfacial tension. The oil-displacement experiment revealed that the EO chains changed the oil recovery and injection pressure by affecting the interfacial tension of the mixed system. This study has significant implications for the formulation design and optimization of agents for oilfield development.

Novel System for the Production of the Bioactive N-alkylamide ‘Spilanthol’ Through Somatic Embryogenesis in Acmella ciliata Kunth (Cass.)

Acmella ciliata Kunth (Cass.), a medicinally important plant in the family Asteraceae, has high commercial value because of its traditional phytomedicinal uses. The plant contains many phytochemicals like alkyl amides, alkaloids, tannins, saponins and flavonoids accountable for most of its pharmacological applications. The study presented here reports the callus culture and somatic embryogenesis of this plant thereby raising a novel system for the subsequent production of the N-alkyl amide ‘spilanthol’, the valuable secondary metabolite presents in it. Murashige and Skoog (MS) medium supplemented with auxins either alone or in combination with cytokinins were used for the induction and maturation of somatic embryos. MS medium supplemented with 2,4-D (0.5, 1.0 and 2.0 mg.L-1) produced black friable callus whereas, 1.0 mg.L-1 NAA in combination with 0.5 mg.L-1 BA induced white, slightly purple coloured friable callus which on further subculture to fresh medium induced somatic embryos that germinated into plantlets upon transfer to MS basal medium. The mode of regeneration via somatic embryogenesis was confirmed by histological analysis through free-hand sectioning and stereomicroscopic observation. The plantlets raised through somatic embryogenesis after a short hardening period, were found to acclimatise in the field at 83.33% efficiency and exhibited genetic uniformity with 96.6% similarity in the ISSR analysis. HPLC analysis of in vitro raised embryogenic callus showed 239.512 µg.g-1 spilanthol content which was comparatively higher than the mother plants (92.19 µg.g-1). The bioproduction of the N-alkylamide ‘spilanthol’ through embryogenic callus can be extended for the scale-up production of this bioactive compound using bioreactor technology for the formulation of phytodrugs.

Palladium-Catalyzed Aerobic Oxidative Spirocyclization of Alkyl Amides with Maleimides via β-C(sp3)-H Activation.

An efficient method for the synthesis of bicyclic spirodiamine molecules via β-C(sp3)-H bond activation of aliphatic amides, followed by cyclization with maleimides, has been developed. The reaction proceeds through an amide-directed β-C(sp3)-H bond activation of alkyl amides and subsequent cyclization with maleimides. The methodology is highly compatible with a wide variety of maleimides. Amides derived from biologically active aliphatic and fatty acids were also found to be highly compatible with the protocol. A palladacycle was synthesized and found to be the active intermediate in this reaction. A plausible reaction mechanism was also proposed to account for this spirocyclization.

Inhomogeneous HfO2 layer growth at atomic layer deposition

Abstract Thin HfO2 films atomic layer deposited from hafnium alkyl amide and oxygen plasma were analysed using spectroscopic ellipsometry and X-ray reflectivity. Low refractive index of the material for samples with less than 30 nm thickness marks the index inhomogeneity at the first stage of growth. The transition from rising density to a more stable growth takes place at about 10 to 25 nm film thickness. HfO2 films used for resistive switching experiments demonstrate either clockwise or counterclockwise behaviour depending on the film thickness. The reason for this may be the disruption of the conductive filament at different metal-insulator interfaces, which could be favoured by several mechanisms.

Molecular Dynamics Study of Silica Nanoparticles and CO2-Switchable Surfactants at an Oil-Water Interface.

Adsorbing CO2-sensitive surfactants on the surface of nanoparticles is an important strategy for preparing stimuli-responsive Pickering emulsions. However, the microscopic mechanisms are still limited, owing to a lack of intuitive understanding at the molecular level on the interactions between nanoparticle and switchable surfactants at the oil-water interface. We employed the molecular dynamics (MD) simulations to explore the mechanism behind the reversible emulsification/demulsification of a Pickering emulsion stabilized by silica nanoparticles (NPs) and CO2-switchable surfactants, named N-(3-(dimethylamino)propyl)alkyl amide (CPMA). MD results show that the protonated surfactant CPMAH+ has strong hydrophilicity, forming an adsorption layer at the oil-water interface. The ionic surfactants can be tightly adsorbed on NP surface through electrostatic interactions. Thus, the formed colloid particle has both hydrophobic and hydrophilic properties, which is a key factor in stabilizing emulsion. When CPMAH+ molecules were deprotonated to CPMA, the hydration activity of the headgroups reduced greatly, inducing a mixture with oil molecules. There are still a certain number of CPMA molecules residing at the oil-water interface due to the hydrophilic amine groups. The results from repeated simulations show that NP can either stay in the water phase or locate at the interface. Even NP was finally adsorbed on the interface and combined with CPMA or oil molecules, the adsorption configuration of CPMA on the NP surface was essentially different from that of CPMAH+. The potential of mean force confirmed that the combination between NP and CPMA is quite unstable due to the disappearance of electrostatic attraction. Different binding configurations and stability between NP and CPMA or CPMAH+ were the fundamental reason for the reversible emulsification/demulsification of Pickering emulsion.

Three cuticular amides in the tripartite symbiosis of leafcutter ants.

Cuticular hydrocarbons (CHCs) play various roles in insects' chemical ecology. As leafcutter ants live in a specific symbiosis with fungi, they harvest and with different bacteria, some of these CHCs might be associated with a mutualistic function within this symbiosis. To obtain a more precise picture in that respect we compared the CHC profiles of the leafcutter ants, Atta sexdens, Atta cephalotes, and Acromyrmex octospinosus inhabited by mutualistic bacteria with the profiles of Polyrhachis dives and Messor aciculatus by GC-EI-MS analysis and 28 other ant species by data from the literature. We were able to identify three alkyl amides (hexadecanamide, hexadecenamide, and tetradecanamide), occurring only in the CHC profiles of leafcutter ants inhabited by symbiotic bacteria. Our results lead to the conclusion that those alkyl amides could have a function in the tripartite symbiosis of leafcutter ants.

Novel octanethioic acid alkyl amide extractants: Synthesis, their highly selective separation for palladium, and the extraction mechanism from chloride media

Highly selective extraction of Pd from leaching liquor of spent auto-catalysts is a research hotspot in recent years. In this study, three novel octanethioic acid alkyl amide extractants (alkyl = butyl TA-804, hexyl TA-806 and 2-ethylhexyl TA-826) were designed, synthesized and characterized by 1H NMR, FT-IR and ESI-HRMS. The effect of contact time, extractant concentration, HCl concentration and diluents on Pd selective extraction and separation by these three extractants were investigated. The stripping behaviors of the loaded Pd in the organic phase were examined. The McCabe-Thiele diagrams of Pd extraction and stripping were drawn. The extraction mechanism was studied through methods of stoichiometry calculation, slope analysis, FT-IR and ESI-HRMS. In the end, the Pd separation from simulated leaching liquor of spent auto-catalysts by TA-804, TA-806 and TA-826 was carried out. The results show TA-826 has much slow Pd extraction kinetics than TA-804 and TA-806. They all have highly efficient extraction and separation performance for Pd from chloride media at acidities of [HCl] ≤ 3 mol/L. When the HCl concentration is ≥4 mol/L, Fe and Pt begin to be extracted. At any acidities, Rh, Zn, Al, La, Zr, Co, Cu, Ni, Ce and Mg are not extracted. The studied octanethioic acid alkyl amides extract Pd from chloride media via complexation mechanism. Two extractant molecules quantitatively extract one Pd. The loaded Pd are easily and efficiently stripped by thiourea. They can efficiently extract and highly separate Pd from leaching liquor of spent auto-catalysts at acidity of 3 mol/L HCl.

Construction of Benzoxazinones from Anilines and Their Derivatives.

Herein we report a strategy concerning Rh(III)-catalyzed direct ortho-C-H bond carbonylation to construct benzoxazinones from anilines and their derivatives with high atom economy. Interestingly, the corresponding amides were generated in situ from anilines when excess Ac2O was added and directed the following C-H bond carbonylation to form benzoxazinones. Extensive functional group tolerance can be achieved when the alkyl amide directing groups were installed. Moreover, this method allows convenient derivatization of some drugs with aryl amine groups to show its potential application.