Study And Application Of Cobalt-Catalyzed C-H Functionalization/Cyclization Of Dicarbonyl Compounds And Olefins

In recent decades,important research progress has been made in the functionalization of alkyne unsaturated bond C-H catalyzed by transition metals,which can efficiently construct complex target compounds.According to research records,transition metals not only have obvious advantages in catalyzing C-H functionalization to synthesize various drugs and chemical products,but also enrich the synthesis ways of nitrogen,oxygen and other heterocyclic rings by catalyzing C-H cyclization of alkyne unsaturated bonds,which lays a good foundation for the application and development of synthetic chemistry and material chemistry.When selecting transition metal catalysts,using A First Row of C-H Functionalized Cheap Transition Metal Catalysts has gained considerable development momentum.In this context,environmentally friendly cobalt complexes have great application potential.Compared with other transition metals such as rhodium,ruthenium,palladium and copper,the C-H functionalization/cyclization reaction catalyzed by organometallic cobalt has become an increasingly feasible tool for step-by-step economic functionalization and assembly of organic molecules.In this paper,cobalt,a relatively cheap transition metal,is used to catalyze dicarbonyl compounds and olefins to develop two new cyclic compounds,which can be effectively used as pharmaceutical intermediates in various natural products and drug molecules.The main contents of this paper include:1.Cp*Co（Ⅲ）-catalyzed C-H functionalization/spiralization of 1,3-indadione and olefin to Synthesize Spirodeindene DerivativesIn this reaction,the C-H functionalization/spirocyclization of 1,3-indanedione with olefins catalyzed by transition metal Co（Ⅲ）was studied,which was used for the synthesis of spiroindene derivatives.In this catalytic process,we investigated the influence of different reaction conditions on it and screened out the most efficient reaction conditions.This effective project has excellent functional group endurance and great atom and step economical efficiency.In the process of cobalt catalytic conversion,1,3-indanedione undergoes a simple oxidative dimerization reaction to obtain an active dimerization intermediate,thus avoiding the complicated procedure of preparing the substrate in advance.In addition,cobalt,the catalyst currently used,is economical and environment-friendly,olefin is easy to obtain,and it has good tolerance in this reaction.It can synthesize a variety of spiroindene derivatives and has good research value as a pharmaceutical intermediate.2.Co（Ⅱ）catalyzes the oxidative cyclization reaction of dicarbonyl compounds and olefins to synthesize cyclopentene and cyclohexene.A unique method for synthesizing cyclopentene and cyclohexene derivatives was obtained by coupling diketones with olefins and dimethyl sulfoxide under the catalysis of Co（Ⅱ）.We also screened out the most efficient reaction conditions.Under the optimal conditions,theα-position substitution of styrene can easily control the formation of five-membered rings and six-membered rings.This process is carried out by oxidative coupling reaction sequence（mediated by K₂S₂O₈）,regioselective olefin insertion（promoted by Co）,and intramolecular attack of allyl cobalt on carbonyl group or methyl group produced in the process of reactive methylene.Cobalt,the catalyst used in our research,is economical,environmentally friendly,olefin is easy to obtain,and has good tolerance in this reaction.It can synthesize a variety of cyclopentene and cyclohexene derivatives and has potential application prospects in the field of drug synthesis.