Application Of Microwave Irradiation In Organic Synthesis

Substituted benzeneacetic acids and dinitrodiphenyl amines are widely applied in many fields, such as medical intermediates, agriculture pesticides, dyes, fuels, heat-sensitive materials, semiconductive materials, and liquid crystal materials etc. It is valuable to study the new synthetic method of them. In this dissertation a series of important results have been obtained.In this dissertation we have synthesized 13 substituted benzeneacetic acids and 13 substituted dinitrodiphenyl amines. All factors which influence the reaction have also been investigated.In the first part of our dissertation we write a comprehensive review on application of microwave irradiation in organic synthesis.In the second part the reactions of acetophenones with sulfur and morpholine under microwave irradiation were studied. The factors influencing the reaction, such as the ratio of substance, microwave power, reaction time and solvent dosage have been investigated. The results showed that this sort of reaction can be finished about 60 minutes under microwave irradiation and the reaction time has been shortened about 16.4 to 25.7 times compared with traditional methods. Thirteen substituted benzeneactic acids were synthesized by the hydrolysis of substituted thioamides in 66-88% overall yields. All of the compounds were characterized by IR spectra, 1HNMR spectra and mass spectra. This new method is fast, simple, and efficient.In the third part the reactions of 2,4-dinitroflorobenzene and substituted benzeneamines under microwave irradiation were studied. The factors influencing the reaction, such as the polarity of solvent, microwave power, reaction time and solvent dosage have been investigated. Thirteen substituted dinitrodiphenylamines were synthesized in 75-94% yield. All of the compounds were characterized by IR spectra, 1HNMR spectra and mass spectra. The results showed that this sort of reaction can be finished within 10 minutes under microwave irradiation and the reaction time has been shortened about 20 to 60 times compared with traditional methods. This new method is fast, simple, and efficient.