Dissertation > Excellent graduate degree dissertation topics show

Study on Synthesis Mechanism of 2-(4-methylpheny) Benzimidazole and Microwave and Infrared Assisted Synthesis of This Reaction

Author: CuiLiJun
Tutor: XiaZhiNing
School: Chongqing University
Course: Chemistry
Keywords: Benzimidazole reaction mechanism microwave-assisted organic synthesis infrared-assisted organic synthesis
CLC: TQ252.3
Type: Master's thesis
Year: 2011
Downloads: 193
Quote: 0
Read: Download Dissertation

Abstract


Benzimidazole is a very important class of heterocyclic compounds with antiviral, antibacterial, anti-inflammatory and other physiological activities, so it has become the focus of research. The reaction of o-phenylenediamine and aldehydes is an important way for the synthesis of benzimidazole, at present the mechanism of this reaction has not been reported. And the mechanism of reaction plays an important role in optimizing the reaction conditions and improving the reaction yield. The microwave technology is widely used in organic synthesis. Compared with conventional heating, microwave heating can increase the yield or shorten the reaction time significantly, and sometimes shows a different selectivity. Infrared is another electromagnetic wave which can provide heat. But infrared is less to be used in organic synthesis. If infrared can promote reactions or change the reaction selectivity as obviously as microwave, it will make a significant impact on the organic synthesis as a more environmentally friendly heating way. In this paper, the synthesis of 2-(4-methylphenyl) benzimidazole was studied for the mechanism of such reactions, and this reaction was heated by microwave and infrared radiation heating. Microwave-assisted the synthesis of N-aryl acetylamines and infrared-assisted the synthesis of isopropyl salicylate were studied, the influence of the radiation heating was investigated.This paper consists of three parts, the main contents are as follows:The first part includes Chapter 2. In this part, the reaction mechanism of the synthesis of 2-(4-methylphenyl) benzimidazole by o-phenylenediamine and aldehydes was studied. The reaction process was monitored by HPLC, and the structures of related intermediates and products were identified by 1H NMR, FT-IR and HPLC-MS. The results indicate that mono-schiff base and bis-schiff base could both be synthesized, and they could form mono-substituted and disubstituted benzimidazole respectively. In addition, it was found that an oxidation process was included in the transformation of mono-substituted benzimidazole from mono-schiff base. Furthermore, proton catalysis was necessary in the formation of disubstituted benzimidazole.The second part includes Chapter 3. In this part, Microwave-assisted and infrared-assisted the synthesis of 2-(4-methylphenyl) benzimidazole by o-phenylenediamine and aldehydes were studied using the commercial microwave synthesis instrument and self-assembly infrared radiation reactor. The influence of the radiation heating was investigated. Under the same experimental conditions, the reaction yield under microwave heating was slightly higher than that under conventional heating, but the difference between them was only 1~10%. There was no significant difference between the reaction yield under infrared heating and conventional heating. Infrared radiation has not promoted the reaction.The third part includes Chapter 4 and 5. In this part, radiation-assisted other organic reactions were studied. First, the reactions for the synthesis of N-aryl acetylamines synthesis were heated by microwave radiation and conventional heating in the same temperature. By comparison of the reaction yields in the two conditions, it was found that microwave radiation could promote reactions, the yields could be increased by 4~25%, and especially the reactions which were difficult to proceed because of the electronic effects. Then, infrared-assisted the synthesis of isopropyl salicylate was studied. The yield of infrared radiation and conventional heating were almost the same, so infrared radiation did not promote this reaction.

Related Dissertations

  1. Synthesis of Benzimidazolium Ionic Liquids and Their Application in Extraction Separation,O626.23
  2. Synthesis and Analysis of Coumarin-fluorescent Probes,O657.3
  3. Containing pyridyl group metal complexes Synthesis and Structure,O627
  4. Heterocyclic acetal -type cationic surfactant synthesis and properties of,TQ423
  5. N-heptane HCCI combustion process temperature thermodynamics and kinetics theory,O643.21
  6. Theoretical Study on Three Miportant Reactions Catalyzed by Nano-Gold Catalysts,O643.32
  7. Theoretical Studies on Reaction Mechanisms and Rate Constants of Several HFEs with OH Radical Reaction,O643.12
  8. Different Versions of the "Chemical Reaction Principle" the Content of Textbooks in the Comparative Study of the Electrochemical,G633.8
  9. Synthesis, Characterization and Catalytic Activity of Polyphenol Oxidase Model Compounds,O643.36
  10. Fluorene and Benzimidazole Based Blue Light-Emitting Copolymers: Synthesis, Photophysical Properties, and PLED Applications,TB34
  11. Studies on the Performance and Mechanism of the Novel Catalysts Loaded with Manganese and Iron for Low Temperatrue NH3 -SCR,TK421.5
  12. The Optimization about the Dynamic Model and Energy Efficiency Analysis of PET Depolymerization under Microwave,O631.3
  13. Determination of Benzimidazoles Residues in Foodstuffs by HPLC-MS/MS,O657.63
  14. Study on the Synthesis of N-N Bond Coupling and Nitrogenous Heterocyclic Compounds Induced by Lanthanide Compounds,O626
  15. Kinetics of Catalysis Hydrolytic Depolym Erization of Poly (ethylene Terephthalate) Under Microwave Irradiation,O631.3
  16. Nucleophilic Research of Benzimizole Carbenes and Seleno-isocyanates,O626.23
  17. Synthesis, Structure and Properties of Organometallic Complexes Based on Benzimidazole Derivatives,O641.4
  18. Synthesis, Characterization and Biolgical Activities of Superoxide Dismutase and Peroxidase Model Complexes,O641.4
  19. Study on Mannich Reactions of Some Heterocyclic Amines,O621.25
  20. Synthesis of Polyimide in Polyphosphoric Acid and Analysis of Structures and Properties of Its Fiber,TQ342
  21. Studies on the Solid Electrolyte Materials of Polybenzimidazole,O633.5

CLC: > Industrial Technology > Chemical Industry > Basic Organic Chemistry Industry > The production of heterocyclic compounds > Containing five pairs or more different atoms of heterocyclic > Between the two nitrogen -mao ( imidazole) and its derivatives
© 2012 www.DissertationTopic.Net  Mobile