Study On The Construction Of Heterocyclic Derivatives Based On O - Haloarylalkene

Construction and transformation of transition-metal catalyzed enyne hydrocarbon compounds is one of the hotspots of modern organic synthetic chemistry.That enyne hydrocarbon compounds progress a series of reactions can provide a convenient and diverse selection for synthesizing pharmaceutical intermediates,pesticides molecular fragment and building the skeleton of biologically active molecules, good chemical reactivity and the diversity of functional group transformations and other features make these compounds are widely used in organic synthetic chemistry and materials chemistry, most of heterocyclic compounds especially furan, thiophene derivatives have good biological activity, and it also have a strong biological activity and are widely used in medicine and pesticide due to its highly active, broad-spectrum, low toxicity and safety, some of derivatives also have good prospects in the fields of industry, dye, new materials. Thereforce, the development of efficient and sustainable methods for the synthesis of thiophene and furan derivatives have great application value. Based on these backgrounds, this thesis mainly includes:1、Study on the terminal alkyne “one-pot” reaction synthesis of 2,5- substituted furan and thiophene compoundsA new method of Cu(I)-catalyzed Glaser coupling and annulation of terminal alkynes for one-pot highly efficient synthesis of 2,5-substituted furan, thiophene,compounds was developed under mild conditions. By optimizing the react conditions filter out the optimum conditions were: terminal alkynes as raw material(1.0 mmol),CuI as a catalyst(5 mol%), TMEDA(10 mol%) as a ligand to promote the coupling reaction, DMSO as solvent(2 mL), the reaction in the presence of oxygen(1 atm) and was set at room temperature for 6 h, then added KOH(Na2S·9H2O)(2 mmol), rising the temperature up to 90 oC and stirred 8 h. Under optimal conditions, we expanded substrate, a yield of 75%~91%(77%~93%) to give 2,5-substituted furan(thiophene)derivatives, while using IR, GC-MS and 1H NMR, 13 C NMR characterized structures of all products and made possible reaction mechanism.2 、 Study on copper-catalyzed 2-fluorophenylacetylene derivatives synthesis of benzofuran compoundsA new method of Cu(I)-catalyzed hydration and annulation of2-fluorophenylacetylene derivatives for one-step-synthesis of benzofuran compounds was developed under mild conditions. By optimizing the react conditions filter out the optimum conditions were: 2-fluorophenylacetylene as raw material(1.0 mmol), CuI as a catalyst(10 mol%), KOH as a strong base(2.0 mmol), KI as an additive(0.2mmol), DMSO as solvent(3 mL), and the reaction was set at 80 oC for 4 h. Under optimal conditions, we expanded substrate, a yield of 76% to 95% to give benzofuran derivatives, while using IR, GC-MS and 1H NMR, 13 C NMR characterized structures of all products and made possible reaction mechanism.3、Study on Na2S·9H2O promoted 2-fluorophenylacetylene derivatives synthesis of benzothiophene compoundsA new method of Na2S·9H2O promoted hydration and annulation of2-fluorophenylacetylene derivatives for the synthesis of benzothiophene compounds was developed under transition-metal-free conditions. By optimizing the reaction conditions filter out the optimum conditions: 2-fluorophenylacetylene as raw material(1.0 mmol), Na2S·9H2O as sulfur(2.0 mmol), DMSO as solvent(3 mL), and the reaction was set at 90 oC for 8 h. Under optimal conditions, we expanded substrate, a yield of 65% to 94% to give benzothiophene derivatives, while using IR, GC-MS and1 H NMR, 13 C NMR characterized structures of all products and made possible reaction mechanism.