Sharif Digital Repository

Present work focuses on the influence of Heteroatom(s) on the bacisity of specific group of amines through the intramolecular hydrogen bonding. This group includes Aza-Crown Ethers specifically. We used Spartan and Gaussian packages to gain optimized structures for all compounds in order to explore the influence of the intramolecular hydrogen bonding on the bacisity of amines. All the gas phase optimizations and energy calculations were performed at the DFT/B3LYP/6-311++G(d,p) level of theory. The Hf/6-31+G(d,p) level was used for all single point calculations in the solution phase. As commonly used solvents in organic and biological reactions, the solution phase calculations were carried... 

In this research, initially the Triethylene glycol and Diglycol amine liquid membrane which is supported by PVDF, was prepared in order to separate the Carbone dioxide from CO2-Air mixture. A polyvinylidene fluoride (PVDF) membrane was chosen to have chemical resistance to solution. The effect of Pressure, Concentration of TEG and DGA solution and the percentage of carbon dioxide in feed; in rate and permeability of CO2, N2 and O2 and also selectivity of CO2/ N2 , CO2/ O2 and N2/ O2 was investigated. Transport of CO2 was facilitated due to reversible chemical reaction between CO2 and amine solution. The experiments were done in 0.4, 0.6 and 0.8bar and different concentration of solution.... 

Sulfur containing compounds are known as the most applicable group of organic compounds. Due to their medicinal and biological applications, dithiocarbamates are the most considerable among the many sulfur containing compounds. There are many procedures reported to synthesize these compounds as synthetic intermediates instead of thiophosgen and isothiocyanates. The reaction of amine and carbon disulfide is reported as the best and least hazardous way to synthesize this functional group. In this project heterocyclic compounds such as thiazoles, thiazolidine-2-thione, and 2-(alkylthio)thiazol-4(5H)-one derivatives were synthesized from the reaction of prepared dithiocarbamates with in situ... 

In this study, density, viscosity and surface tension of aqueous solution of Sulfolane, ( TEA+TMS+H2O) and (DIPA+TMS+H2O) systems were measured . Density, viscosity and surface tension were measured using pycnometer, Cannon – Fenske viscometer and Capillary rise method, respectively. Surface tension measurements of (DIPA+TMS+water) were carried out by the ring method using a LAUDR TD3 tensiometer,. The experiments were carried out in low concentrations and atmospheric pressure in the temperature range (70 - 30) . The obtained Data was modeled using empirical and thermodynamic models. Density calculation was done using the Setchenov and Redlich – Kister models.and the results indicated that... 

This project investigates on synthesis of β-amino carbonyl compounds with new approach to become closer to green chemistry principals.In this project, we investigated the synthesis of β-amino carbonyl compounds with aromatic amines and electron deficient alkenes in the Michael reaction using boric acid and glycerol in water as a green media. High yields of the products and easy handling are some advantages of this procedure. Also, we investigated the Michael reaction in different solvents and temperatures but gave better results in the aqueous media. Moreover, thiomorpholine derivatives were synthesized using this method to give excellent yield.
 

The fused pyrimidine rings have many biological applications such as antibacterial, antiviral, antitumor and anti-inflammation activity. Therefore, their synthesis has attracted many attentions. In this thesis, the synthesis of fused pyrazolopyrimidine rings through two component reaction catalyzed by iodine was investigated. In this reaction, iodine is used to active the imine bond. Low toxicity, availability, low cost and stability to air are some benefits of iodine as a Lewis acid leading to widespread application of I2 in many different organic transformation. Mild reaction conditions, high yields and lower reaction times are among the main advantage of these reactions.
Another part... 

Natural gas contains small amount of benzene, toluene, ethyl benzene and meta-xylene (BTEX). These compounds are soluble in amine solutions and accumulate in aqueous amine solution during sour gas removal process. They produce problems such as foaming in amine adsorption columns. The aim of this work is to study BTEX removal from aqueous amine solution by means of activated carbon. Three different commercially available granular activated carbons were used in experiments. Experiments were divided in static and dynamic adsorption categories. In the static tests, equilibrium adsorption of all three activated carbons were performed and the most effective activated carbon sample determined by... 

In recent years, nanodiamond (ND) has been used as reinforcement in polymeric nanocomposites in order to improve mechanical properties, thermal conductivity, etc. The surface of nanodiamond has several functional groups which make it appropriate adsorbent. In this study, nanodiamond was modified with dodecylamine corrosion inhibitor and was utilized (1wt %) in epoxy based nanocomposite. Fourier transform infrared spectroscopy (FTIR) analysis was used to confirm the surface modification of Nanodiamond. In order to estimate the loading amount of corrosion inhibitor, thermogravimetric analysis was investigated. FE-SEM analysis demonstrated nanoparticle dispersibility in epoxy matrix. Regarding... 

This research project contains two parts that investigating new approaches for becoming closer to green chemistry principals is clear in it. In the first part we tried to synthesis dithiocarbamate salts using aromatic amins and than Michael addition of them to prepare bifunctional dithiocarbamats. But we found ?-thiols as final product. In the second part of this project, we investigated the regioselective epoxide ring opening with aromatic amines by using boric acid and glycerol in water as a green media. Corresponding ?-amino alcohols were obtained with excellent yields and considerable regioselectivity. High yields of the products, mild reaction conditions, using green catalyst and water... 

Removal of some hazardous and toxic components of natural gas is of a great importance in industries. Thus solubility measurement of these components in appropriate solvents is a necessary task. Methylmercaptan due to its high toxicity as one of these components is separated by means of Alkanolamines. In this project a physical solubility experimental setup for absorption Methylmercaptan (CH3SH) in 48wt%, 35wt% and 25wt% MDEA aqueous solutions at 50°C and in pressures between (0.7 to 3)bar was designed and developed. The suggested setup can be used for measurement of solubility of gases (physical and chemical) in different solutions. The performance basis of the system is on precise... 

Donor-acceptor adducts of selenium dioxide were formed with tree aromatic amines, two aliphatic amines and tree pyridine like bases. Characterization of these adducts were done through UV-Vis Spectrophotometer and IR Spectrophotometer and NMR Spectroscopy. In addition, the stoichiometry of these adducts were identified by elemental analysis (CHN). To approve the existence of selenium, Atomic absorption instrument was used.The results obtained from the entioned methods show that the adduct formation between selenium dioxide with amines and pyridine like bases are in following order: p-phenylen diamine.SeO2>NH5.SeO2,en.SeO2,cyclohexylamine.SeO2,... 

Polyurethanes are polymers prepared by the reaction of polyols with isocyanates. Due to the wide range of raw materials from which polyurethanes are synthesized, as well as their various applications, they are classified into several groups, of which polyurethane foams are one of the most important products that have significant consumption. One of the most important diisocyanates is methylene diphenyl diisocyanate and also one of the most commonly used polyols in the polyurethane industry are polyesters.In addition, chain extenders, catalysts and suitable additives such as foaming agents, surfactants, fillers, etc., are all raw materials that participate in the production of polyurethane... 

The purpose of this study is to prepare platinum nanoparticles catalysts whitch can be used to C-H activation processes. In order to increase platinum salt catalytic activity, by converting it into a catalyst with characteristics of having recovery cycles, convenient separation and environmental friendliness and being in nano size. Consequently, platinum nano particles were grafted on modified graphene oxides. Catalysts structures were verified by scanning electron microscope, fourier transform infrared spectroscopy, X-ray diffraction, and energy dispersive spectroscopy. Subsequently catalytic activity was examined for C(sp3)-H activation reaction with 3 amines and C-C bond formation. A... 

In the first section, a novel and efficient multicomponent reaction for the synthesis of polysubstituted pyrrolidine derivatives is described under catalyst-free conditions using unltrasonic irradiation. The reactions were performed via a one-pot four-component condensation of secondary amines, carbon disulfide, isocyanides, and gem-dicyano olefins at room temperature to afford polysubstituted pyrrolidines diastereoselectively in 56-96% yields. This is the first report of Mumm-type rearrangement with dithiocarbamates followed by intramolecular cyclization which lead to the preparation of the key structure of pyrrolidine.In the second section, an efficient and unprecedented green protocol... 

Due to the increasing concentration of greenhouse gases in the earth's atmosphere and their destructive consequences, many scientists and researchers have turned to preventing the emission of greenhouse gases, such as carbon dioxide. One of the primary sources of carbon dioxide emissions is flue gases. Carbon dioxide is one of the most important greenhouse gases, the release of which causes global temperature increase and climate change. One of the options for reducing carbon dioxide emissions from gas streams is using reactive amine solvents, considered the most critical technologies for carbon dioxide removal. The only commercially available carbon dioxide separation method is absorption... 

With considering the existence of carbonyl sulfide in natural gas and crude oil, we need to study the absorption of this gas in aqueous alkanolamine solutions. In this project the solubility of carbonyl sulfide in different pressures and two temperatures of 313.15 and 348.06 K have been measured.The absoption of carbonyl sulfide in aqueous alkanolamine solutions is a very slow process. In this study we used different methods for measuring the required data. Befor the experiments we calibrated the set up with reliable data. Finaly the results simulated with Deshmakh-Mather thermodynamic model, numerically. The simulation results show a good agreement with experimental data