Catalyst-free Synthesis Of Oxygen,Nitrogen-containing Heterocyclic Compounds Under Microwave Irradiation

The discourse consists of four parts.The first part involves the reviews of organic reactions under catalyst-free and microwave-promoted organic reactions under catalyst-free, which prompt us to investigate in this filed.The second part involves the synthesis of heterocyclic compounds containing oxygen atom.α,α-bis(4-hydroxycoumarin-3-yl)toluene derivatives were synthesized by using aromatic aldehyde and 4-hydroxycoumarin in water without any catalyst under microwave irradiation. Particularly valuable features of this method include shorter reaction time, excellent yields of the products, straightforward procedure and environmental friendliness.The third part involves the synthesis of heterocyclic compounds containing nitrogen atom. A series of 2-(3-coumarinyl)quinoxaline derivatives was synthesized by the reaction of 3-(α-bromoacetyl)coumarins with substituted 1,2-diaminobenzenes in the absence of any catalyst under microwave conditions in the first section. The second section involves the synthesis of biologically active quinoxaline derivatives from the condensation of o-phenylenediamines with. The reactions were carried out under catalyst-free, solvent-free and microwave irradiation conditions. In the third section, one-pot synthesis of 2,4,5-triaryl imidazoles by cyclocondensation of 1,2-dicarbonyl compounds, aldehydes, and ammonium acetate. Particularly valuable features of this method include shorter reaction time, excellent yield of the products, straightforward procedure and environmental friendliness.In the forth part, we lay out some compounds'spectrogram of the 1H NMR, 13C NMR and Ms...