Study On The Synthesis Of Heterocyclic Compounds Through Transition Metal Catalyed C-H Functionalization

Heterocyclic compounds are an important class of organic compounds.Many natural and synthetic heterocyclic compounds have potential pharmacological activities and photoelectric activity.In addition,they have been wide used in chemical synthetic drugs and natural products.Transition metal-catalyzed C-H functionalization has been proved to be a powerful organic synthesis method.Therefore,it is of great significance to use this method to construct heterocyclic compounds with potential biological activity.This dissertation focuses on the synthesis of N-containing and O-containing heterocyclic compounds by the transition metal-catalyzed carbon-hydrogen bond functionalization.The main contents are as following:1.Selective Synthesis of Alkynylated Isoquinolines and Biisoquinolines via Rh^IIIII Catalyzed C-H Activation/1,3-Diyne Strategy.Described herein is a convenient and highly selective synthesis of alkynylated isoquinolines and biisoquinolines from various aryl ketone O-pivaloyloxime derivatives and 1,3-diynes via rhodium-catalyzed C-H bond activation.In this transformations,alkynylated isoquinolines,3,4'-and 3,3'-biisoquinolines could be obtained respectively through changing the reaction conditions.Mechanistic investigation revealed that the C-H activation of aryl ketone O-pivaloyloxime was the key step to this reaction.2.One-pot Synthesis of Alkynylated Coumarins via Rhodium-Catalyzed Annulation of Aryl Thiocarbamates with 1,3-Diynes or Terminal Alkynes.A convenient and selective synthesis of alkynylated coumarins from various aryl thiocarbamates and 1,3-diynes or terminal alkynes via rhodium-catalyzed C-H bond activation has been developed.In this transformation,both symmetrical and asymmetrical 1,3-diynes could be applicable,obtaining various 3-alkynylated coumarins in moderate to excellent yields.When the substituent is aryl group,the resulting compounds were found to exhibit intense fluorescence in the range of412–443 nm with quantum yield of up to 0.57 in CH₂Cl₂.Moreover,the internal alkynes were readily converted to 1,2-dione,olefins,alkanes,and bisheterocycles under certain conditions.