Sharif Digital Repository

Herein, we report an efficient one-pot four-component reaction of commercially available 1,3-dicarbonyl compounds, aromatic aldehydes, amines, and nitromethane in the presence of ZnO nanoparticles, which leads to highly substituted pyrroles in moderate to good yields. A mild and efficient tandem process for the synthesis of highly substituted α-pyrones starting from 2-arylacetic acid of high com-mercial availability has been developed. The synthesis is based on the Knoevenagel condensation of 1,3-cyclohexadiones to various β-keto-Esters, followed by lactonization in the presence of 20 mol% ZnO as a nanocatalyst. Moderate to high yields, easily available and less expensive starting materials... 

In the last few decades due to technological progress and more attention to cost reduction of production, production systems have become more automated than before. By increasing the role of machines in manufacturing systems maintenance systems have become more important. One of the factors that influence the complexity of maintenance problem in real world is the interdependency of components in a system. Interacting cooperation between these components intensifies the complexity of the problem’s modeling as well as its optimizing. This complexity result in few studies that have been performed in this field. Thus these works can be broken into two main subjects. In the first case a system... 

In the first chapter, high substituted pyrrole derivaitives were synthesized through a one pot four compounent reaction using carbonyl and amin compounds at the presence of magnetic nanoparticles of superparamagnetic ferrospinel NiFe2O4nanoparticles as catalyst.In the second chapter, NiFe2O4magnetic nanoparticles were employed in the Sonogashira reactions using phenyl acetylene as coupling partner with different types of aryle and alkyl halides in water as a green solvent. The results of these reactions were considered comprehensively  

In first part Mesoporous silica (SBA-15) was synthesized by template synthesis method and the surface of SBA-15 was functionalized with 3-glycidoxypropyltrimethoxysilane and 5-Phenyl-1H-tetrazole. Palladium nanoparticles were immobilized on the aforementioned mesoporous support. Characterization of catalyst regarding to its structure, morphology and other parameters was investigated by physiochemical analysis such as XRD, SEM, TEM, and TGA. This heterogeneous catalyst has high capability in reduction of nitrobenzenes and selective oxidation of primary alcohols which respectively gain aminoarenes and benzaldehydes in high yields. Reduction and oxidation reactions are done in water as a green... 

Nowadays, using one-pot multicomponent reactions in the synthesis of organic and natural compounds has attracted a lot of attention due to their ideal synthetic features. These types of reactions play an important role in synthetic chemistry by reducing reaction steps, costs, wastes, and by-products and increasing the reaction efficiency as an efficient method. The issue that led to this project was the development of a novel procedure for developing synthetic methods for the synthesis of thioxo-pyrrolidine 3-carbutamide compounds. In this study, the first Mumm rearrangement was performed by using dithiocarbamates by applying ultrasonic irradiation. The reaction was investigated in methanol... 

Nowadays, heterocyclic compounds have become extremely important in various industries, especially the pharmaceutical industry.In this project, an efficient and environmentally friendly path is presented to synthesize numerous rhodanine-oxindole derivatives in polyethylene Glycol in one pot-four components procedure. This pathway doesn't need harsh reaction conditions such as high temperature, long time, catalysts, complicated separation steps, toxic solvents, etc. all products have been made under green strategy with high yield.
 

In the present research, a numerical model is developed based on extended finite element method to simulate single phase multicomponent fluid flow through naturally fractured porous media containing explicit fractures. Each of fracture and porous matrix are separate continuous media that interact with each other due to fluid and solute exchange. The governing equations involve continuity equation of fluid phase and mass conservation equation of one component. The extended finite element method allows for explicit and accurate representation of cracks to capture the mass transfer of fluid components between fracture and matrix. Existence of fracture in the domain results in discontinuity of... 

Porous burner technology has many advantages in comparison with conventional burners such as higher burner thermal performance, lower pollutants emission, high power ranges, fuel flexibility, compact geometry and higher turn down ratios. These kinds of burners are made of preheated porous combustion zone and combustion porous zone that have different thermophysical and geometrical properties. In this work, the transient one-dimensional multi-step premixed laminar reacting flows in a two-stage porous media burner have been investigated. The combustible mixture is considered H2-Air (9 species and 19 reactions) and CH4-Air (22 species and 49 reactions). In porous media, without lateral wall... 

In this study the transport and deposition of pharmaceutical particles delivered by a commercial metered dose inhaler (MDI) is investigated in a combination of human upper airways, inhaler, and spacer. The emphasis of the present work is on the effects of evaporation of ethanol from particles, inlet momentum of particles, and use of spacer on their transport and deposition phenomena. The pharmaceutical particles are typically delivered with high initial momentum to human upper airways. It is believed that this initial momentum is responsible for increased undesirable deposition of particles in upper airways, especially in case of particles larger than 1 micrometer in diameter. In the present... 

An efficient one-pot procedure is described for the synthesis of derivatives of 3,4-Dihydrochromen-2-ones under solvent-free and metal-free conditions via a pseudo-four-component domino reaction of acetic anhydride, aryl aldehydes, glycine-based dithiocarbamates, and phenols/naphthols. All products were made under green strategy with high yields