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Published in Eli Ruckenstein, Hangquan Li, Chong Cheng, Solution and Surface Polymerization, 2019
Eli Ruckenstein, Xiaonong Chen
Cross-Linking of Polymers Containing Tertiary Amine Pendants. Five α, ω-dihalides were employed as cross-linkers for the polymers containing tertiary amine pendant groups, such as BA-DMAEA copolymer (PBN in Table 2.4.1), St-DMAEA copolymer (PSN in Table 2.4.1), and PVP. As shown in Table 2.4.4, the gelation times of PSN and PVP were 20 (N8) and 13 min (N15), respectively, at room temperature (ca. 24°C), for α,α′-dibromo-p-xylene (DBX) as cross-linker, indicating a high cross-linking reactivity of this dihalide. No gelation was reached, however, when PSN and PVP were reacted with a monohalide, such as benzyl bromide (BzB,N14) and benzyl chloride (BzC, N21), respectively, at large halide/amine mole ratios and a high temperature (100°C) for as long as 26 h. These results clearly indicate that the formation of covalent ionene bridges and not the ion pair interactions was responsible for the cross-linking of these polymers. No gelation was, however, observed for 1,4-dichlorobutane (DCB) as cross-linker, indicating a low reactivity of the primary chlorine of the DCB. As expected, the cross-linking reactivity decreased in the carbonium ion character sequence DBX > DCA > DCX > DBB > DCB.
Interfacial Catalysis at Oil/Water Interfaces
Published in Alexander G. Vdlkdv, Interfacial Catalysis, 2002
The effects of added water on the rates of displacement of benzyl bromide and benzyl chloride with KCN salt in toluene catalyzed by 18 -crown- 6 were reported [145]. It was observed that a small amount of water considerably increased the reaction rates compared to the anhydrous conditions and that the rate increased sharply to a maximum value in the presence of an optimum amount of added water. An important observation was that under anhydrous conditions, the reaction followed zero-order kinetics while in the presence of added water it followed first-order kinetics. It was suggested that the initial small amounts of added water coated the surface of the salt particle, which extracted the crown ether from the organic phase to form a new interfacial region called the “omega (ω) phase.” It was believed that the catalytic reaction took place mainly in the omega phase, since the quantity of added water corresponding to the maximum quantity of crown ether on the surface of the salt particles correlated well with the optimum quantity of added water.
Organic Synthesis
Published in Suresh C. Ameta, Rakshit Ameta, Garima Ameta, Sonochemistry, 2018
Chetna Ameta, Arpit Kumar Pathak, P. B. Punjabi
Ando and Kimura (1991) demonstrated a reaction between benzyl bromide and alumina-supported potassium cyanide in toluene. Benzyl cyanide was produced by nucleophilic displacement of the bromine by supported cyanide, but substituted toluene was obtained without sonication.
Evaluation of structure-reactivity correlation of efficient corrosion inhibitor ionic liquids for mild steel in acidic medium
Published in Journal of Dispersion Science and Technology, 2023
Ashish Rathore, Shobhana Sharma, Ankit Sharma, Sushil Kumar Sharma
Ionic liquid inhibitors have the general formula IL where [X = Br−, Cl−]. The microwave-assisted synthesis of disubstituted imidazolium cation-based ionic liquids requires the interaction of an equimolar amount of 1-ethyl imidazole and benzyl bromide/benzyl chloride [benzyl bromide for IL-1 and benzyl chloride for IL-2] at 78 °C, as outlined in Scheme 1. The yellow-colored imidazolium cation-based ionic liquids are obtained by washing with ethyl acetate and drying in a vacuum oven. These viscous ionic liquids are soluble in water and other polar solvents. The monomeric nature of N, N dialkyl imidazolium cation-based ionic liquids implies by mass spectroscopy. Table 1 provides the physical data of imidazolium cation-based ionic liquids. The physicochemical and spectral studies help to elucidate the structures of these ionic liquid inhibitors. Computational modeling offers further deep insight into structural information.
Design and synthesis of silver nanoparticle anchored poly(ionic liquid)s mesoporous for controlled anticancer drug delivery with antimicrobial effect
Published in International Journal of Environmental Health Research, 2022
Ehsan Aliakbari, Yahya Nural, Reza Eghdam Zamiri, Erdal Yabalak, Mehri Mahdavi, Vahid Yousefi
N-vinyl imidazole, divinyl benzene, azobisisobutyronitrile, benzyl bromide, silver nitrate, and ethylene glycol were purchased from Merck and Sigma-Aldrich. All solvents used were of reagent grade quality and were used without further purification. Fourier transform infrared spectra of the synthesized nanomaterials were recorded over the range of 400–4000 cm−1 region by using a Thermo Nicolet model Nexus 870 FT-IR spectrometer. The synthesized nanomaterial was illustrated by TEM (Philips EM 208S). The specific surface area was determined from the linear part of the BET plot, and the pore size distribution was calculated from the adsorption branch using the Barrett – Joyner–Halenda (BJH) method analyzer (BELMAX, Japan), and synthesized-nanocatalyst was first degassed at 80°C for four h. TGA was carried out using a simultaneous TG apparatus (Linseis model L81A1750 Germany). The rate of the absorbance of the drugs was measured by UV – vis spectroscopy (UV-1700 Pharma Spec, Shimadzu).
Evaluation of Cu(II) bzimpy complexes by 1H-NMR and catalytic activities
Published in Journal of Coordination Chemistry, 2020
Synthesized compounds were characterized by elemental analysis and NMR and IR spectra. The bzimpy ligands were synthesized according to the steps illustrated in Scheme 1. At the first step, 2,6-bis(benzimidazol-2-yl) pyridine (1a) and 2,6-bis(5,6-dimethylbenzimimidazol-2-yl) pyridine (2a) were prepared by reaction of pyridine-2,6-dicarboxylic acid with o-phenylenediamine and 4,5-dimethylbenzene-1,2-diamine in polyphosphoric acid (PPA). Bzimpy ligands (1b–d, 2b–d) were obtained via the alkylation of 1a and 2a with benzyl chloride, 2,4,6-trimethylbenzyl bromide, and pentamethyl benzyl bromide in the presence of KOH in acetone at reflux. The ligands (1b–d, 2b–d) are soluble in chlorinated solvents, alcohols, and DMSO. In 1H-NMR spectra, the Py-Hp and Py-Hm protons were observed as doublets and triplets in a 2:1 ratio at around δ 8.11–8.56 ppm. Signals at δ 45.8–48.1 ppm corresponded to the benzylic methylene carbon resonances for 1b–d and 2b–d.