Open Access. Powered by Scholars. Published by Universities.®

Engineering Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 7 of 7

Full-Text Articles in Engineering

Synthesis And Research Of Silicon-Containing Phthalocyanine, Dilmurod Shukurov, Hayit Turayev, Abdulakhat Djalilov, Masud Karimov Oct 2021

Synthesis And Research Of Silicon-Containing Phthalocyanine, Dilmurod Shukurov, Hayit Turayev, Abdulakhat Djalilov, Masud Karimov

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of this study is to synthesize, and study a new form of dye based on phthalocyanine, a silicon-containing phthalocyanine pigment used as a dye for dye-sensitive solar cells, which are currently third generation solar cells as one of the energy source alternatives. To achieve this goal, a silicon-containing phthalocyanine pigment containing urea, phthalic anhydride and sodium fluorosilicate was synthesized and studied. Based on the results of IR spectroscopy, the reaction of pigment formation is proposed and the data of scanning electron microscopy is presented. Its differential thermal analysis, photodynamic analysis and its relationship with inorganic and organic solvents …


Synthesis Of Aromatic Acetylene Alcohols Using Complex Catalytic Systems, Odiljon Ziyadullaev, Guzal Otamukhamedova, Abduvakhab Ikramov, Saida Abdurakhmanova, Otabek Boytemirov May 2021

Synthesis Of Aromatic Acetylene Alcohols Using Complex Catalytic Systems, Odiljon Ziyadullaev, Guzal Otamukhamedova, Abduvakhab Ikramov, Saida Abdurakhmanova, Otabek Boytemirov

CHEMISTRY AND CHEMICAL ENGINEERING

Some cyclic ketones (cyclopentanone, cyclohexanone, 2-methylcyclohexanone, menthol, camphor and adamantanone) enantioselective alkynylation reactions with phenylacetylene have been studied in the presence of complex catalytic systems - Zn(OTf)2/NЕt3/MeCN, 3,3′-Ph2BINOL-2Li/TGF and BuLi/KOtBu/TGF. Synthesis were performed new aromatic acetylene alcohols – 1-(2-phenylathinyl) cyclopentanol (1), 1-(2-phenylethinyl)cyclohexanol (2), 2-methyl-1-(2-phenylethinyl)cyclohexanol (3), 2-isopropyl-5-methyl-1-(2-phenylethinyl)cyclohexanol (4), 1,7,7,-trimethyl-2-(2-phenylethinyl)bicyclo [2.2.1] heptanol-2 (5) and 2-phenylethinyltricyclo [3,3,1.03,7]nonanol-2 (6). Synthesis reactions of aromatic acetylene alcohols, activation energies were determined, kinetic of chemical changes and reaction mechanisms were proposed. The course of the reactions and the effect of the selected ketone molecule size, structure and …


Heterogeneous Catalytic Conversions Of Acetylene, Abduvakhab Ikramov, Sevara Kholikova, Noryigit Musulmanov May 2021

Heterogeneous Catalytic Conversions Of Acetylene, Abduvakhab Ikramov, Sevara Kholikova, Noryigit Musulmanov

CHEMISTRY AND CHEMICAL ENGINEERING

The reactions of interaction of acetylene with water vapor, acetic acid and ammonia in the presence of heterogeneous catalysts have investigated. Depending on the nature of the starting components used, acetaldehyde and acetone, vinyl acetate, pyridine bases and pyrrole synthesized. Heterogeneous catalysts selected for each studied reaction based on some scientific prerequisites for the selection of catalysts. Active catalysts for the investigated reactions were determined, which contain compounds of cadmium, zinc, bismuth, chromium, iron and copper, in general, d-group metals. γ-Al2O3, bentonite and kaolin used as a catalyst carrier. Hydrofluoric acid, acetic acid, ammonium fluoride and …


Synthesis Of Some N-Oxides Of Pyridylacethylene Amines Based On 2-Methyl-5-Ethynylpyridine, Abduvakhab Ikramov, Odiljon Ziyadullayev, Adkham Khamidjanov, Shavkat Bojariev, Davron Khandamov Apr 2021

Synthesis Of Some N-Oxides Of Pyridylacethylene Amines Based On 2-Methyl-5-Ethynylpyridine, Abduvakhab Ikramov, Odiljon Ziyadullayev, Adkham Khamidjanov, Shavkat Bojariev, Davron Khandamov

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of this work is to study the reaction of 2-methyl-5-ethynylpyridine N-oxide with some aliphatic and aromatic amines to obtain N-oxides of pyridylacetylenic amines. 2-Methyl-5-ethylpyridine converted to 2-methyl-5-vinylpyridine by dehydrogenation, and 2-methyl-5-ethynylpyridine obtained by bromination and dehydrobromination. 2-methyl-5-ethynylpyridine N-oxide synthesized by oxidation of 2-methyl-5-ethynylpyridine with perhydrol in acetic anhydride. The synthesis of N-oxides of pyridylacetylenic amines by the Mannich reaction carried out. The effect of the solvents: methanol, ethanol and n-dioxane, the catalyst, and the reaction time on the yield of the final product studied. The structure and composition of the synthesized PAA N-oxides were established using IR and …


The Role Of Hydrogen Bonds In Diluted Ethanol Solutions Of Cyclohexane And Dimethylformamide, Dilbar Bozorova, Shukur Gofurov, Mavlonbek Ziyayev, Dildora Mirtojiyeva, Odina Ismanova, Oksana Ismoilova Apr 2021

The Role Of Hydrogen Bonds In Diluted Ethanol Solutions Of Cyclohexane And Dimethylformamide, Dilbar Bozorova, Shukur Gofurov, Mavlonbek Ziyayev, Dildora Mirtojiyeva, Odina Ismanova, Oksana Ismoilova

CHEMISTRY AND CHEMICAL ENGINEERING

The refractometric method and Fourier transform infrared spectroscopy were used to determine the optical features of the concentration characteristics of diluted ethanol solutions of cyclohexane and dimethylformamide. It was found for the first time that at some concentrations the hydrogen bond is stronger than for a pure ethanol solution. The first maximum of the excess refractive index of solutions is formed at a concentration of 0.02 mole fraction of cyclohexane and dimethylformamide, which is in good correlation with IR spectroscopy, indicating the largest number of formed hydrogen bonds.


Ethinylation Reactions Of Some Aldehydes In The Presence Of Phenylacetylene Using High-Base Catalytic Systems, Abdurakhmanova Saida, Ikramov Abduvaxab, Ziyadullayev Odiljon, Ablakulov Lochin Feb 2021

Ethinylation Reactions Of Some Aldehydes In The Presence Of Phenylacetylene Using High-Base Catalytic Systems, Abdurakhmanova Saida, Ikramov Abduvaxab, Ziyadullayev Odiljon, Ablakulov Lochin

CHEMISTRY AND CHEMICAL ENGINEERING

The aim of the research work is the development of synthesis methods of aromatic acetylene alcohols and their various derivatives using different catalytic systems and also, determining their structure, physico-chemical and biological properties. The most effective way of synthesizing AAA is determined using selected complex catalytic systems and also, the range of catalytic activity of used catalysts is created. Acetic aldehyde, benzaldehyde and cyclohexonal, high-base catalytic systems − MOH/ДМСО∙H2O and M2CO3/ДMСO∙H2O with phenylacetylene reaction of enantioselective etynilation were investiged. Efficiency and course of chemical reaction in the process of formation acetylene alcohol affection of temperature, reaction duration, solvents, catalysts and …


Synthesis Of Meta-Altered Arylmaleinamide And Preparation Of Esters In Their Presence, Turaeva Khurshida, Yuldasheva Mukhabbat, Khaydarova Sadokat Feb 2021

Synthesis Of Meta-Altered Arylmaleinamide And Preparation Of Esters In Their Presence, Turaeva Khurshida, Yuldasheva Mukhabbat, Khaydarova Sadokat

CHEMISTRY AND CHEMICAL ENGINEERING

The development of new methods of synthesis using cheaper reagents for the preparation of maleic acid derivatives, the study of chemical properties and the determination of new directions for the practical application of maleic acid derivatives are still relevant. Therefore, the development of this work is an urgent task. The aim of this study was to obtain the synthesis of monomaleinamide compounds under various conditions to obtain arylmaleimide derivatives of maleic acid and to transfer them in a pure state for further reactions. In this study, scientific studies were carried out to find convenient methods for the preparation of monoamide …