Cu-catalyzed The Synthesis Of Polysubstituted Furans And Pyrroles In The Presence Of O₂

In the first chapter, we have reviewed methodology for the synthesis of polysubstituted furans. The methods of synthesizing polysubstituted furans have been developed in the past years, such as classica Paal-Knorr reaction, Feist-Benary reaction, multi-componets "one-pot", transition metal catalyzed tandam reaction, C-H activation, and so on. Recently the C-H activation and cross-dehydrogenative-coupling reaction for the construction of heterocycles with simple and readily accessible substrates have received great attention and would have a brilliant prospect for its economic, sustainable and environmentally friendly features. We have developed a novel and straightforward synthesis of polysubstituted furans was achieved easily from oxidative cyclization of 1,3-dicarbonyl compound and alkynoate catalyzed by Cul in the presence of O2. The procedure is simple, sustainable and environmentally benign. In addition, the starting materials are readily available. Oxygen is used as the oxidant in the synthesis of polysubstituted furans which would accelerate the green synthetic methods to approach substituted furans.In the second chapter, we have reviewed methodology for the synthesis of polysubstituted pyrroles, such as classica Paal-Knorr reaction, Hantzsch reaction, multi-componets "one-pot", transition metal catalyzed tandam reaction, C-H activation, and so on. Especialy, the alkynoates as an important substrat have been used to synthesize the polysubstituted pyrroles. Due to the important application of polysubstituted pyrroles, the field of pyrroles suntheses is continuously received tremendous interest. We have developed a facial and straightforward method for the synthesis of polysubstituted pyrroles was achieved easily from oxidative cyclization ofβ-enamino ketones or esters and alkynoates catalyzed by Cul in the presence of O2 We have developed a facial and direct method for construction polysubstituted pyrroles. Variation of N-substituents, aromatic ring, alkyl-and ester was proven possible and this reaction can proceed smoothly in moderate to good yields. Molecular oxygen was used as the oxidant in the synthesis of polysubstituted pyrroles.In the third chapter, we have introduced the operating instruction of chemical and rapid determination of melamine in liquid milk. Our method use the solid acid to extract the melamine from liquid milk and erich it by eluting solvent, then the flitered solvent react with precipitant to produce the precipitate.Observed the precipitate to determinate the liquid milk whether contain melamine or not with your eyes. This method have the advantages, such as lower limit of determination (≥2ppm), high-speed,,cheap and simple.