Electrochemistry-promoted Cascade Construction Of Spiro Dihydrofuran、Pyran、Quinoline、3-hydroxy-indol-2-one Skeleton

The discourse includes five parts.The first part invovles the applications of electrocatalytic organic reactions and the basis for the selection of the subject and the creative points.In part two, an one-pot synthesis of spiro dihydrofuran derivatives via the reaction of aldehyde and dimedone at room temperature in ethanol by electrochemistry was described. This method had valuable features including short reaction time, excellent yields of the products, straightforward procedure and environmental friendliness.In the third part, we presented an one-pot synthesis of pyran derivatives via the condensation of aldehyde, malononitrile and 1,3-dicarbonyl compounds at room temperature in ethanol by electrocatalysis. This protocol featured short reaction time, high yields, easy work-up, and environmentally friendly procedure. This method provided an efficient and promising synthetic strategy to expand pyran derivatives of diversity.The fourth part introduced the synthesis of a series of 4-substituted--3,5,7,7-trimethyl-1-phenyl-6,7,8,9-tetrahydro-1H-pyrazolo[3,4-b]quinolin-5(4H)-one derivatives via electrocatalytic reaction of aldehyde, 3-methyl-1-phenyl-1H-pyrazol-5-amine and dimedone at room temperature in ethanol by electrocatalysis. This chemistry provided a new compound library with potential activity for biomedical screening. In order to extend the scope of application of the method, we also synthesized series of 2-amino-7,8,9,10-tetrahydro-pyrimido[4,5-b]quinoline-4,6(3H,5H)-dione derivatives via by the reaction of aldehyde, 2,6-diamino-pyrimidin-4(3H)-one and dimedone at room temperature in aqueous media by electrocatalysis.The fifth part put forward an one-pot synthesis of 3-hydroxy-indol-2-one derivatives via isatin and 3-methyl-5-amino-1-phenyl-1H-pyrazole at room temperature in aqueous media by electrocatalysis. This method provided an efficient and promising synthetic strategy to expand diversity of 3-hydroxy-indol-2-one derivatives of diversity. Besides, a novel series of compound library with potential activity for biomedical screening was built.All products were characterized by IR, 1H NMR and HRMS. Furthemore, the structures of some products were confirmed by 13 C NMR and X-ray analysis.