Oxidative Coupling/Cyclization Reaction Involving Amine

Organic synthetic chemistry is widely used in the production of drugs,chemical products,and functional materials,and is closely related to the development of human life.The transition metal catalyzed coupling reaction has promoted the rapid development of organic synthesis methodology.From cross couplings between electrophiles and nucleophiles to oxidative couplings between two nucleophiles,this represents another leap in organic synthesis chemistry.The oxidation cross-coupling reaction based on the direct bonding of two C-H/X-H compounds represent the frontier of coupling reaction research.And it is in line with the needs of green friendship,economic efficiency and social sustainable development.On the other hand,organic nitrogen compounds are widely found in nature and have extremely important physiological effects.Starting from the N-H compounds,the direct installation of organic nitrogen compounds into organic molecules through oxidative coupling has important practical significance and broad application prospects.At first,the paper briefly reviewed the oxidative coupling reactions and the applications of organic nitrogen compounds in medicine and pesticide materials.Then the paper introduced the development of oxidative coupling of N-H compounds.The content of this paper is based on organic compounds,through the rational design of the use of electrochemical oxidation,palladium catalyzed oxidative carbonylation,to achieve the organic nitrogen-containing alkylation,formylation,cyclization reaction.More details are as following:1.A method for electrooxidative C(sp3)-H amination via intermolecular oxidative C(sp3)-H/N-H cross-coupling has been developed under metal-and oxidant-free conditions.The C(sp3)-H bonds adjacent to oxygen,nitrogen and sulfur atom could all react smoothly with various amines to give corresponding products with moderate to good yields.In addition,the C(sp3)-H bonds of benzylic and allylic are also tolerated in this reaction.A preliminary mechanistic study indicates that the C-H cleavage of tetrahydrofuran is probably not involved in the rate-determining step and pyrazole is preferentially oxidized in the reaction system2.We demonstrate a simple protocol that the amide carbon-nitrogen bond can be oxidative activated and cleaved by Na2S2O8.This transformation provides an efficient path for the synthesis of various formamides with good to excellent yields.3.A method uses DMF as a methyl source to achieve quinolinone construction was reported.This method utilizes cheap and readily available DMF as a raw material to successfully complete the construction of quinazolinones under metal-free conditions,providing a new choice for the construction of quinolones under mild conditions.4.A novel method of palladium-catalyzed oxidative carbonylation of ketones,amines and CO for the synthesis of 4-quinolones has been developed.This protocol provides a straightforward route to construct useful 4-quinolone derivatives from inexpensive chemicals.At the same time,the reaction is carried out under balloon pressure CO/O2,there is no special requirement on the reaction device.