Condensation Reaction Of Aniline Research Articles

Synthesis of multilayer polymer-immobilised nanosilver for catalytic study in condensation reaction of aniline and acetylacetone

Silver nanoparticles were synthesized in green route with non-hazardous polyvinyl alcohol and polyvinylpyrrolidone as stabilizing as well as reducing agents and water as green solvent. This silver nanoparticle-embedded polymer composite film, Ag/PVA–PVP was characterized by UV–Vis spectroscopy, SEM and TEM. The catalytic activity of this film was evaluated in reduction of p-nitrophenol, acylation of aniline and synthesis of a β-enaminone, 4-phenylamino-pent-3-en-one with appreciably good results. β-enaminone synthesis reaction was chosen to study the effects of kinetic parameters such as reactant quantity, catalyst loading, solvents and temperatures. In a typical reaction, 89% conversion was achieved. A probable chemical reaction mechanism is suggested. Kinetic model fitting for the synthesis of β-enaminone reaction was done for the first time here. Heterogeneous kinetic model following Eley-Rideal pathway showed an excellent data fitting for the reaction. The rate law parameters were estimated. Scheme. Synthesis and catalytic application of multilayer polymer-immobilised nanosilver in condensation reaction of aniline and acetylacetone.

Synthesis of 4,4′-Methylenedianiline Catalyzed by SO3H-Functionalized Ionic Liquids

4,4′-Methylenedianiline (4,4′-MDA) is a key intermediate for the production of polyurethanes. A series of SO3H-functionalized ionic liquids (SFILs) were synthesized, and their catalytic performance was evaluated in the condensation reaction of aniline with formaldehyde for the synthesis of 4,4′-MDA. The result showed that SFILs had excellent catalytic activity, and their catalytic activity was consistent with their acid strength. [HSO3-bmim]CF3SO3 (SImTf) with the highest acid strength showed the best catalytic activity. Then, the influence of reaction conditions on the condensation reaction of aniline with formaldehyde to 4,4′-MDA was investigated using SImTf as the catalyst, and suitable reaction conditions were obtained as follows: molar ratio of aniline to formaldehyde = 5, mass ratio of SImTf to formaldehyde = 3.5, reaction temperature of 80 °C, and reaction time of 8 h. Under the above reaction conditions, the conversion of aniline was 36.3%, and the yield and selectivity of 4,4′-MDA were 79.4% and ...

Aza-crown ether complex cation ionic liquids: preparation and applications in organic reactions.

Aza-crown ether complex cation ionic liquids (aCECILs) were devised, fabricated, and characterized by using NMR spectroscopy, MS, thermogravimetric differential thermal analysis (TG-DTA), elemental analysis and physical properties. These new and room-temperature ILs were utilized as catalysts in various organic reactions, such as the cycloaddition reaction of CO2 to epoxides, esterification of acetic acid and alcohols, the condensation reaction of aniline and propylene carbonate, and Friedel-Crafts alkylation of indole with aldehydes were investigated carefully. In these reactions, the ionic liquid exhibited cooperative catalytic activity between the anion and cation. In addition, the aza-[18-C-6HK][HSO4]2 was the best acidic catalyst in the reactions of esterification and Friedel-Crafts alkylation under mild reaction conditions.

Insights on the mechanism for synthesis of methylenedianiline from aniline and formaldehyde through HPLC–MS and isotope tracer studies

The mechanism for synthesis of 4,4-methylenedianiline (MDA) via condensation reaction of aniline with formaldehyde has been studied extensively in this paper. The intermediate and by-products were isolated and identified. The combination of isotope labeling and HPLC–MS characterizations disclosed that the reaction proceeded through an SN2 reaction mechanism. Moreover, the effect of aniline/formaldehyde molar ratio on the formation of MDA was investigated. This work would be of significance to understand the reaction mechanism deeply and provide valuable information for further improving the yield of desired product.

Non-catalytic condensation of aromatic aldehydes with aniline in high temperature water

The synthesis of diamino triphenyl methanes from aniline and aromatic aldehydes was conducted in near critical water and supercritical water. The reaction parameters, such as temperature, density, and reaction time, have been studied. Significant acceleration of the condensation reaction of aniline and aromatic aldehydes can be achieved by using high temperature water, especially near the critical point, in the absence of any acid catalysts. It has been demonstrated that high temperature water act effectively in the place of conventional acid catalysts.

Monofunctional benzoxazine from cardanol for bio-composite applications

In this study, a monofunctional benzoxazine monomer was synthesized by condensation reaction of aniline and formaldehyde with cardanol, a by product of cashew nut shell liquid (CNSL). The monomer was characterized by FTIR and 1H NMR spectral analysis. Curing characteristics were studied by differential scanning calorimeter. The exothermic peak associated with curing was observed from 230 °C to 291 °C with a peak maximum of 272 °C. Adding a small percentage of cardanol as phenolic initiator reduced the onset of cure as well as peak maximum temperature due to accelerated curing. Thermo gravimetric analysis indicated a peak decomposition temperature of 432 °C and a char yield of 24% at 800 °C. The viscoelastic properties of the neat cardanol benzoxazine, its jute fiber composite and the acrylonitrile modified jute fiber composites were studied with dynamic mechanical thermal analyzer (DMTA). The storage modulus ( E′) value increased with fiber loading and showed a higher value for treated composite indicating an increase in interaction between fiber and resin matrix. On the other hand, the tan δ which is associated with glass transition, shifted to lower value compared to neat resin with incorporation of jute fibers.

HPW and supported HPW catalyzed condensation of aromatic aldehydes with aniline: Synthesis of DATPM derivatives

The mesoporous Si-MCM-41 was synthesized by hydrothermal method and various wt.% (20 and 30 wt.%) of HPW were loaded on Si-MCM-41 by wet impregnation method. The synthesized Si-MCM-41 and HPW-loaded catalysts were characterized by XRD, BET surface area, FT-IR, TEM and TGA–DTG techniques. The catalytic activity of the catalyst was tested over the condensation reaction of aniline with various aromatic aldehydes at refluxing temperature under liquid-phase condition, which yields highly commercial product namely diamino triphenyl methanes (DATPMs). The effects of various parameters like catalyst, mole ratio, solvents and substituent effect on the formation of DATPMs were optimized. The catalytic activity of the catalysts showed the following order: H 3PW 12O 40· nH 2O > H 3PMo 12O 40· nH 2O > H 4SiW 12O 40· nH 2O > 20 wt.% HPW/MCM-41 > 30 wt.% HPW/MCM-41 > HM (12) > Hβ (8) > HY (4) > HZSM-5 (15) > Al-MCM-41 (25). The results showed that mole ratio of 4:1 (aniline:aldehyde) gave higher yield than the other mole ratios. Acetonitrile and ethyl acetate shows better activity especially in the supported materials than toluene was used as a solvent. The product thus obtained was analyzed by 1H NMR, FT-IR techniques.

Toughening of epoxy resin with amine functional aniline acetaldehyde condensate

AbstractThe diglycidyl ether of bisphenol‐A (DGEBA) resin was modified with amine functional aniline acetaldehyde condensate (AFAAC) and cured with an ambient temperature curing agent triethylene tetramine. The resulting networks displayed significantly improved fracture toughness. The AFAAC was synthesized by the condensation reaction of aniline and acetaldehyde in the acid medium (pH 4) and characterized by FTIR and NMR spectroscopy, elemental analysis, viscosity measurements, and mole of primary and secondary amine analysis. The DGEBA and AFAAC were molecularly miscible but developed a two‐phase microstructure upon network formation. Epoxy/AFAAC compositions were systematically varied to study the effect of AFAAC concentration on the impact, adhesive, tensile, and flexural properties of modified networks. The dynamic mechanical analysis and scanning electron microscopy studies showed two phase morphology in the cured networks, where AFAAC particles were dispersed. The AFAAC modified epoxy network was thermally stable up to around 280°C. POLYM. ENG. SCI., 47:1695–1702, 2007. © 2007 Society of Plastics Engineers

Lanthanide(III) ion as a luminescent and catalytically active reaction center of aniline condensation with butyraldehyde

A new type of chemiluminescence catalytic conversion in which the lanthanide(III) ion is a luminescent and highly efficient catalytically active center was found. Chemiluminescence (CL) is generated in the condensation reaction of aniline with butyraldehyde in DMF to form 3-ethyl-2-propylquinoline. The reaction is catalyzed by LnCl3·6H2O (Ln = Eu, Tb, and Ho). When EuCl3·6H2O and TbCl3·6H2O salts are used as catalysts, the CL emitters are the Eu3+* and Tb3+* excited ions. In the case of HoCl3·6H2O, the emitter is 3-ethyl-2-propylquinoline in the triplet-excited state.

Catalytic activity of zeolites for synthesis reaction of methylenedianiline from aniline and formaldehyde

The catalytic activities of Y-, β-, and ZSM-5-zeolites for methylenedianiline (MDA) synthesis from the condensation reaction of aniline and formaldehyde have been investigated. Among β-zeolites with various Al concentrations (Si/Al ratios from 10 to 120 mol mol −1), β-zeolite with Si/Al ratio of 13.6 mol mol −1 shows the best catalytic performance in MDA synthesis. Y-zeolite exhibited lower catalytic activity than β-zeolites under the identical reaction conditions, however, exhibited the higher selectivity to 4,4′-MDA. Furthermore, it revealed that aniline/formaldehyde and catalyst/formaldehyde ratio, and reaction temperature also influenced on the MDA yield and isomers distribution.

Functionalization of hydroxy compounds with nitrilotriacetic acid for technetium-99m chelation: Excretory properties of the radiolabelled chelates

Substituted monoanilides of nitrilotriacetic acid (NTA) have gained much popularity in recent years as an important class of ligands for technetium-99m ( 99mTc) radiopharmaceutical preparations used in liver imaging and function studies. We were interested in investigating the properties of the corresponding ester analogues of this important class of ligands and for this study cyclohexanol was selected as a hydroxy component, which on condensation with nitrilotriacetic acid in the presence of acetic anhydride, furnished the monoester, N-cyclohexyloxycarbonylmethyl iminodiacetic acid 4 and the corresponding diester 5. Phenol on similar condensation produced mainly the diester, N, N-di(phenyloxycarbonylmethyl) aminoacetic acid 2, with traces of the corresponding monoester 7. A reinvestigation of the well known condensation reaction of aniline with nitrilotriacetic acid revealed that in addition to the reported monoanilide, N-phenylcarbamoylmethyl imino diacetic acid 3, the corresponding dianilide 6 was also produced in appreciable amount. The ester ligands 2, 4, 5 after 99mTc chelation exhibited good in vitro and in vivo stabilities. The biodistribution characteristics of these radiolabelled esters and amides were very similar showing thereby that esterification with NTA could be an effective method for converting alcohols to 99mTc-radiopharmaceuticals without generating any unusual properties because of the ester linkage. Residual radiopharmaceutical concentration after i.v. administration of these amide and ester 99mTc chelates at 30 min in blood, urine, liver, kidney and intestine were correlated with their lipophilicities and during this correlation it was observed that in addition to lipophilicity the anionic strength of these chelates is also an important determinant in governing their biodistribution. The ester ligand 4 after 99mTc chelation showed ultrafast hepatobiliary kinetics and was therefore compared in a rabbit model with a standard hepatobiliary radiopharmaceutical 99mTc- N-( p-butylphenylcarbamoyl methyl) iminodiacetic acid ( 99mTc-BIDA) by γ-camera scintigraphy to investigate the potential of the former for clinical studies.