58175-55-6Relevant academic research and scientific papers
Small-angle neutron-scattering studies of mixed micellar structures made of dimeric surfactants having imidazolium and ammonium headgroups
Pal, Asish,Datta, Sougata,Aswal,Bhattacharya, Santanu
, p. 13239 - 13247 (2012)
Planar imidazolium cation based gemini surfactants [16-Im-n-Im-16], 2Br- (where n = 2, 3, 4, 5, 6, 8, 10, and 12), exhibit different morphologies and internal packing arrangements by adopting different supramolecular assemblies in aqueous media depending on their number of spacer methylene units (CH2)n. Detailed measurements of the small-angle neutron-scattering (SANS) cross sections from different imidazolium-based surfactant micelles in aqueous media (D2O) are reported. The SANS data, containing the information of aggregation behavior of such surfactants in the molecular level, have been analyzed on the basis of the Hayter and Penfold model for the macro ion solution to compute the interparticle structure factor S(Q) taking into account the screened Coulomb interactions between the dimeric surfactant micelles. The characteristic changes in the SANS spectra of the dimeric surfactant with n = 4 due to variation of temperature have also been investigated. These data are then compared with the SANS characterization data of the corresponding gemini micelles containing tetrahedral ammonium ion based polar headgroups. The critical micellar concentration of each surfactant micelle (cmc) has been determined using pyrene as an extrinsic fluorescence probe. The variation of cmc as a function of spacer chain length has been explained in terms of conformational variation and progressive looping of the spacer into the micellar interior upon increasing the n values. Small-angle neutron-scattering (SANS) cross sections from different mixed micelles composed of surfactants with ammonium headgroups, 16-A 0, [16-Am-n-Am-16], 2Br- (where n = 4), 16-I0, and [16-Im-n-Im-16], 2Br- (where n = 4), in aqueous media (D 2O) have also been analyzed. The aggregate composition matches with that predicted from the ideal mixing model.
gemini-type imidazole surfactant with high-temperature thickening effect Wormlike micelle and application thereof
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Paragraph 0027; 0028; 0030, (2021/11/21)
The invention relates to gemini-type imidazole surfactant, wormlike micelle and application thereof in the technical field of surfactants, and the formula of gemini-type imidazole surfactant with the high-temperature thickening effect of the invention is [C]. n - C2 - Cn im] Br2 (n=16, 18). The gemini-type imidazole surfactant has high stability and viscoelasticity at high temperature under one-component conditions in water. The specific structure enables the wormlike micelle with high-temperature thickening effect to be formed without additives in water. And [C]n - C2 - Cn im] Br2 (n=16, 18) The concentration in the aqueous phase was 91 - 143 mmol ? L. -1 At the time of 25 - 97 °C temperature range, the system behaves as a wormlike micelle with excellent thermal stability, so that [C] of the invention is made. n - C2 - Cn im] Br2 (n=16, 18) The high-temperature vermicular micelle formed in water can be used as an oil-displacing agent for tertiary oil recovery. Soft templates for synthetic nanomaterials, lubricants, and the like.
N-Functionalised Imidazoles as Stabilisers for Metal Nanoparticles in Catalysis and Anion Binding
Beer, Paul D.,Cookson, James,Serpell, Christopher J.
, p. 683 - 690 (2020/07/03)
Metal nanoparticles (NPs) have physicochemical properties which are distinct from both the bulk and molecular metal species, and provide opportunities in fields such as catalysis and sensing. NPs typically require protection of their surface to impede aggregation, but these coatings can also block access to the surface which would be required to take advantage of their unusual properties. Here, we show that alkyl imidazoles can stabilise Pd, Pt, Au, and Ag NPs, and delineate the limits of their synthesis. These ligands provide an intermediate level of surface protection, for which we demonstrate proof-of-principle in catalysis and anion binding.
Surface-active double-alkaline task-specific ionic liquids and preparation method thereof
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Paragraph 0036-0039; 0046-0049; 0056-0059, (2019/08/12)
The invention relates to surface-active double-alkaline task-specific ionic liquids and a preparation method thereof. The surface-active double-alkaline task-specific ionic liquids are synthesized bythe following three-step reactions: firstly, performing coupling on imidazole and a halogenated hydrocarbon under alkaline conditions to obtain N-long chain alkyl imidazole; secondly, performing a quaterisation reaction on the N-long chain alkyl imidazole and 1-(2-chloroethyl)piperidine hydrochloride to obtain an ionic halide; and finally, performing ion exchange to obtain the target molecular hydrogen hydroxide N-long chain alkyl imidazole alkaline ionic liquids. The synthetic method provided by the invention has mild reaction conditions and simple post-treatment; and the ionic liquids not only have double functions of Lewis alkalinity and Bronst alkalinity, but also have surface active functions.
Molecular tunability of surface-functionalized metal nanocrystals for selective electrochemical CO2 reduction
Pankhurst, James R.,Guntern, Yannick T.,Mensi, Mounir,Buonsanti, Raffaella
, p. 10356 - 10365 (2019/11/20)
Organic ligands are used in homogeneous catalysis to tune the metal center reactivity; in contrast, clean surfaces are usually preferred in heterogeneous catalysis. Herein, we demonstrate the potential of a molecular chemistry approach to develop efficient and selective heterogeneous catalysts in the electrochemical CO2 reduction reaction (CO2RR). We have tailor-made imidazolium ligands to promote the CO2RR at the surface of hybrid organic/inorganic electrode materials. We used silver nanocrystals for the inorganic component to obtain fundamental insights into the delicate tuning of the surface chemistry offered by these ligands. We reveal that modifying the electronic properties of the metal surface with anchor groups along with the solid/liquid interface with tail groups is crucial in obtaining selectivities (above 90% FE for CO), which are higher than the non-functionalized Ag nanocrystals. We also show that there is a unique dependency of the CO2RR selectivity on the length of the hydrocarbon tail of these ligands, offering a new way to tune the interactions between the metal surface with the electrolyte and reactants.
An efficient strategy for N-alkylation of benzimidazoles/imidazoles in SDS-aqueous basic medium and N-alkylation induced ring opening of benzimidazoles
Chakraborty, Ankita,Debnath, Sudipto,Ghosh, Tanmoy,Maiti, Dilip K.,Majumdar, Swapan
, p. 5932 - 5941 (2018/09/18)
A sustainable route for the N-1 alkylation of imidazole and benzimidazole derivatives has been developed under volatile organic solvent free condition in alkaline water-SDS system. Incorporation of SDS in the reaction medium enhances the reaction rate by suppressing the solubility issue that arises for different substrates. This method provides high yield of the alkylated product in a shorter reaction time. For reactive alkyl halides reaction proceeds at ambient temperature whereas in the cases of less reactive alkyl halides require 55–60 °C to complete alkylation process. N-alkylation induced ring opening of the heterocyclic ring in benzimidazole derivatives to multifunctional aromatic compounds were noticed at 60 °C when more than two equivalents of alkyl halide was used.
Exploring the cellular uptake and localisation of phosphorescent rhenium: Fac -tricarbonyl metallosurfactants as a function of lipophilicity
Hallett, Andrew J.,Placet, Emeline,Prieux, Roxane,McCafferty, Danielle,Platts, James A.,Lloyd, David,Isaacs, Marc,Hayes, Anthony J.,Coles, Simon J.,Pitak, Mateusz B.,Marchant, Sarah,Marriott, Stephen N.,Allemann, Rudolf K.,Dervisi, Athanasia,Fallis, Ian A.
supporting information, p. 14241 - 14253 (2018/10/25)
A systematic study of the cellular uptake of emissive complexes as a function of their lipophilicity is presented. Here a series of amphiphilic rhenium fac-tricarbonyl bisimine complexes bearing axial substituted imidazole or thiazole ligands, [Re(bpy)(CO)3(ImCnHm)]+ {n = 1 m = 3 (1+), n = 4 m = 9 (2+), n = 8 m = 17 (3+), n = 12 m = 25 (4+), n = 16 m = 33 (5+), n = 2 m = 3 (6+); bpy = 2,2′-bipyridine, Im = imidazole} and [Re(bpy)(CO)3(L)]+ {L = 1-mesitylimidazole, ImMes (7+), 4,5-dimethylthiazole, dmt (8+) and 4-methyl-5-thiazole-ethanol, mte (9+)} is reported. The X-ray crystal structures of 2+, 8+ and 9+ confirm the geometry and expected distribution of ligands and indicated that the plane of the imidazole/thiazole ring is approximately parallel to the long axis of the bipy ligand. Luminescence studies revealed excellent properties for their use in cell imaging with visible excitation and broad emission profiles. Their uptake in two distinct species has been examined by fluorescence imaging of the diplomonad fish parasite Spironucleus vortens (S. vortens) and rod-shaped yeast Schizosaccharomyces pombe (Schiz. pombe) as a function of their lipophilicity. The uptake of the complexes was highest for the more lipophilic 2+-5+ in both S. vortens and Schiz. pombe in which the long alkyl chain aids in crossing bilipid membranes. However, the increased lipophilicity of longer chains also resulted in greater toxicity. Localisation over the whole cell varied with differing alkyl chain lengths with complex 2+ preferentially locating to the nucleus of S. vortens, 3+ showing enhanced nuclear partitioning in Schiz. pombe, and 4+ for the remaining cell wall bound in the case of S. vortens. Interestingly, complexes of intermediate lipophilicity such as 7+ and 8+ showed reasonable uptake, proved to be non-toxic, and were capable of crossing exterior cell walls and localising in the organelles of the cells.
1,1 the [...] -di-alkyl -3,3 the [...] -(2-phosphate ester -1,3-propyl) imidazole in the process for the preparation of salt compound
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Paragraph 0079; 0080, (2016/12/07)
The invention relates to a 1,1'-dialkyl-3,3'-(2-phosphate-1,3-propylidene)imidazolium compound and a preparation method thereof. The structural formula of the 1,1'-dialkyl-3,3'-(2-phosphate-1,3-propylidene)imidazolium compound is shown in the specification, wherein n is 6, 8, 10, 12 and 14, and the alkyl imidazole can be replaced with alkyl benzimidazole. The 1,1'-dialkyl-3,3'-(2-phosphate-1,3-propylidene)imidazolium is a amphoteric dimeric surfactant, and a concrete synthesis method comprises the following steps: synthesizing 1, 3-dichloro-2-propanol, synthesizing N-alkyl imidazole, synthesizing 1,1'-dialkyl-3,3'-(2-hydroxyl-1,3-propylidene)imidazole hydrochloride, and synthesizing 1,1'-dialkyl-3,3'-(2-phosphate-1,3-propylidene)imidazolium. The 1,1'-dialkyl-3,3'-(2-phosphate-1,3-propylidene)imidazolium compound and the preparation method are easily available in raw materials, the reaction technology conditions are easy to control, operation is simple, the product is easy to purify, and yield is high. The compound has low critical micelle concentration, and can be used as a wetting agent, an emulsifier, a foaming agent and a foam stabilizer. A molecular structure has macrocyclic cefpimizole group and phosphate ester, and thus the compound has good thermal stability, solubility, salinity resistance, temperature resistance and acid and base resistance.
A Comprehensive Study on the Synthesis and Micellization of Disymmetric Gemini Imidazolium Surfactants
Zhao, Xiaohui,An, Dong,Ye, Zhiwen
, p. 681 - 691 (2016/07/06)
Two groups of disymmetric Gemini imidazolium surfactants, [C14C4Cmim]Br2 (m?=?10, 12, 14) and [CmC4Cnim]Br2 (m?+?n?=?24, m?=?12, 14, 16, 18) surfactants, were synthesized and their structures were confirmed by 1H NMR and ESI–MS spectroscopy. Their adsorption at the air/water interface, thermodynamic parameters and aggregation behavior were explored by means of surface tension, electrical conductivity and steady-state fluorescence. A series of surface activity parameters, including cmc, γcmc, πcmc, pC20, cmc/C20, Γmax and Amin, were obtained from surface tension measurements. The results revealed that the overall hydrophobic chain length (Nc) for [C14C4Cmim]Br2 and the disymmetry (m/n) for [CmC4Cnim]Br2 had a significant effect on the surface activity. The cmc values decreased with an increase of Nc or m/n. The thermodynamic parameters of micellization (ΔGm θ, ΔHm θ, ΔSm θ) derived from the electrical conductivity indicated that the micellization process of [C14C4Cmim]Br2 and [CmC4Cnim]Br2 was entropy-driven at different temperatures, but the contribution of ΔHm θ to ΔGm θ was enhanced by increasing Nc or m/n. The micropolarity and micellar aggregation number (Nagg) were estimated by steady-state fluorescence measurements. The results showed that the surfactant with higher Nc or m/n can form larger micelles, due to a tighter micellar structure.
Imidazolium salts grafted on cotton fibres for long-term antimicrobial activity
Izmaylov, Boris,Di Gioia, Diana,Markova, Galy,Aloisio, Irene,Colonna, Martino,Vasnev, Valery
, p. 22 - 28 (2015/01/30)
New antimicrobial (AM) coatings based on imidazolium salts have been prepared linking the imidazolium salts to the cotton fabric using siloxane oligomers as coupling agents. Three different imidazolium salts, linked to the siloxane oligomers connected to
