Rhodium-Catalyzed C-H Activation For Synthesis Of Cyclic Compounds

Transition-metal-catalyzed C-H functionalization has developed as a powerful tool for cyclic compounds synthesis over past decades.Among these metal catalyst,Rh-catalyst is most prominent due to its high reactivity,functional group tolerance and compatibility for scope of substrates,especially for Cp*Rh(?).1.We conclude the research progress of Rh-Catalyzed activation from directed group.The research status of Rh-Catalyzed carbonyl,amine,imine,N-heterocycle,amide and sulfur-containing group directed C-H bond activation.2.Rh(?)-Catalyzed Enaminone-Directed Alkenyl C-H Activation for the Synthesis of Salicylaldehydes.we have reported herein a Rh(?)-catalyzed enaminone-directed alkenyl C-H activation method for coupling with alkynes and synthesis of salicylaldehydes.This represents a synthetically unique example of benzene ring framework formation through transition metal-catalyzed directed C-H activation strategy.The two reactive functionalities(aldehyde and hydroxy groups)generated along the way provide a powerful synthetic handle for further structural manipulation.3.Synthesis of Isoindoles via Rh(?)-Catalyzed N-chloroimine-Directed C-H Coupling with ?-Diazo-?-phosphonoacetates.we have developed herein a Rh(?)-catalyzed N-chloroimine-directed C-H activation for synthesis of isoindoles,with ?-Diazo-?-phosphonoacetates.We obtained the Rh-five-member ring complex to explain mechanism of Rh(?)-catalyzed N-chloroimine-directed C-H activation.Isoindoles are regarded as OLEDs cause of their electroluminescent and high fluorescent properties,and their structure units are common in biologically active molecules and dyes.The reaction features dephosphonation of phosphonoacetate group of ?-Diazo-?-phosphonoacetates by N-Cl bond to cyclize under low catalyst loading.Afforded a wide range of isoindoles skeleton which have diverse applications,such as OLEDs,biologically active molecules and dyes.Most of the products have good to excellent yields,meanwhile this reaction just needs mild condition and have wide scope of substrates,which means it is perspective method for synthesis of isoindoles.4.Synthesis of Isoquinolines via Rh(?)-Catalyzed N-chloroimine-Directed C-H Functionalization.We have proposed an N-chloroimines-directed C-H functionalization method and proved its practicability of synthesis of methylisoquinolines by coupling with alkynes.The reaction takes full advantage of high reactivity of N-Cl bond of N-chloroimines,which proceeds a series of advantages:mild reaction conditions;significantly,reaction in green solvent;internal oxidation pathway;atom-economic;broad substrate scope.