Optical Response of Poly (1,4-Phenylene-1,2-Di (P-Phenoxyphenyl) Vinylene) Towards Oxygen Gas

This research involved the synthesis of poly (1,4-phenylene-1,2-di (p-phenoxyphenyl) vinylene), dpop-PDV from di (p-phenoxybenzoyl) benzene compound as the monomer. The potential of the produced polymer as sensing reagent for O2 detection based on fluorescence quenching was studied. Di (p-phenoxybenzoyl) benzene was synthesised via the Friedel-Crafts benzoylationwith terephthaloydichloride and biphenylether as starting materials and anhydrous AlCl3 as the catalyst, while the dpop-PDV was synthesized via the McMurry coupling reaction. The polymerization was carried out in THF with TiCl4 and Zn as the catalyst and reducing agent respectively. Characterization on monomer and polymer had been carried out by using FTIR, GCMS, DSC, TGA, GPC and melting point measurement. Response of the polymer towards oxygen gas was described in terms of fluorescence spectra, repeatability, reproducibility and the response curve. Results obtained showed that the fluorescence intensity decreased upon exposure to O2 gas, indicating that the polymer was responsive to the presence of the O2 gas and the sample was found regenerable by flushing the polymer solution with N2 gas.

Application of plackett-burman design to benzylation of o-cresol with benzyl alcohol

Plackett-Burman design was employed to study the reaction of o-cresol with benzyl alcohol in the presence of anhydrous aluminium chloride as catalyst for screening variables. The variables chosen for the investigation were temperature, molar ratio of o-cresol to benzyl alcohol, amount of anhydrous AlCl3 catalyst (% by wt. of o-cresol), addition time (ta h), stirring time (ts h), stirring speed (rpm). Among these variables temperature, molar ratio of o-cresol to benzyl alcohol and amount of anhydrous AlCl3 were found to be important. A set of trials was planned according to a 3 factor 2-level Yates pattern experimental design with 2 replicates and the center point trial with 4 replicates. The critical response was the yield of benzyl o-cresol. Main effects as well as two- and three- factor interaction effects were statistically significant. A polynomial model was developed and the adequacy of the suggested model was checked up.Bangladesh J. Sci. Ind. Res. 50(3), 169-180, 2015

Synthesis of sec.-undecylbenzene and sec.-dodecyl benzene by alkylation

The title compounds were synthesized by the alkylation of benzene with olefins (undecene-1 and dodecene-1) in presence of borontrifluoride etherate and alcohols (undecan-1- ol and dodecan-1- ol) with anhydrous AlCl3. The effect of temperature, molar ratio of benzene to olefins & alcohols, amount of catalyst were studied. The highest yield was 73.6% in case of dodecene-1 and in case of undecene-1 was 70.6%. Dodecan-1-ol was found to be more reactive than undecanl-1-ol but the yields were higher in olefins than alcohols. DOI: http://dx.doi.org/10.3329/bjsir.v49i1.18848 Bangladesh J. Sci. Ind. Res. 49(1), 9-12, 2014

NMR Spectral Correlations in Some Tröger’s Bases

Some Tröger’s bases have been synthesised from substituted anilines and paraformaldehyde in presence of Lewis acid catalyst such as anhydrous AlCl3, through electrophilic substitution reaction. The purities of these Tröger’s bases have been checked by their physical constants and spectroscopic data published earlier in the literature. The NMR chemical shift (δ, ppm) of methylene protons and carbon were assigned. The assigned methylene protons and carbon chemical shifts (δ, ppm) of synthesised Tröger’s bases have been correlated with Hammett substituent constants, F and R parameters using single and multi-regression analyses. From the results of statistical analyses, the effects of substituent on methylene protons and carbon were discussed.

Synthesis of 1, 2-Aceanthrylenedione Catalyzed by Anhydrous AlCl3

1,2-aceanthrylenedione was synthesized through the acylation reaction of anthracene and oxalyl chloride catalyzed by anhydrous AlCl3. The effects of various reaction conditions on the yield and selectivity of 1, 2-aceanthrylenedione were studied by GC analysis. The results show that the optimum synthesis conditions of the acylation reaction are as follows : the molar ratio of oxalyl chloride to anthracene being 1:2, the molar ratio of anhydrous AlCl3 to anthracene being 4:1, the reaction time being 5 h, the reaction temperature being 303k and the solvent of the reaction system being CS2. Under those conditions, the yield and selectivity of 1, 2-aceanthrylenedione is 83.8 % and 92.3% respectively. Pure 1, 2-aceanthrylenedione was prepared by extraction and recrystallation. The structure of 1, 2-aceanthrylenedione was identified by measure of melting point, GC/MS, FTIR and 1HNMR analyses.

Electrorefining of aluminum alloy in ionic liquids at low temperatures

The electrorefining of aluminum alloy (A360) in ionic liquids at low temperatures has been investigated. The ionic liquid electrolyte was prepared by mixing anhydrous AlCl3 and 1-Butyl-3- methylimidazolium chloride (BMIC) in appropriate proportions. The effect of the cell voltage temperature, and the composition of the electrolyte on the electrorefining process has been studied. The characterization of the deposited aluminum was performed using scanning electron microscopy (SEM) and X-ray diffraction (XRD) techniques. The influence of experimental parameters such as cell voltage and concentration of AlCl3 in the electrolyte on the deposit morphology was discussed. The composition of the aluminum deposits was analyzed using X-ray fluorescence spectrometer (XRF). Aluminum deposits with purity higher than 99.89 % were obtained. At a cell voltage of 1.0 V vs. Al/Al(III), the energy consumption was about 3 kWh/kg-Al. The main advantage of the process is low energy consumption compared to the existing industrial aluminum refining process.