Studies On Sp~3 C-H Bond Activation Of Allylic/Propargyl Coumpounds With Benzoquinones

With the emergence of the concepts of "atom economy" and "green chemistry", research of directly using C-H bonds to form new C-C bonds and C-hetero bonds via C-H activation has attracted more and more attention recent years. Via C-H bond activation methodology, the reaction steps of the functionalization of many compounds can be shortened, this helped to improve the atom economy and reduce the pollution of the environment. Also, C-H activation provides researchers new approach to synthesize a series of natural products and bioactive molecules. And our group has paid much attention on intermolecular Cross-Dehydrogenative-Coupling (CDC) reactions recent years.Allylic and propargyl compounds are very useful structures of many intermediates, but the synthesis of allylic and propargyl coumpounds was seldom reported recently. So we explored the CDC reactions of allylic and propargyl compounds to form a series of important structures via C-H bond activation.The research mainly contains four fields as follows:Firstly, we have developed an efficient Palladium-Catalyzed oxidative indolation reaction of allylic compounds via sp C-H bond activation under mild condition. This enriched the types and structures of indoles, providing a strategy to screen for the bioactive molecules.Second, iron-promoted synthesis of substituted 1-Halo-1,4-pentadienes by reaction of 1,3-diarylpropenes with ethynylbenzenes via sp3 C-H bond activation has been realized. This reaction also provides a new way to build a series of halogenated diolefins.Third, in the absence of metal catalyst, we further realized directly using allylic compounds and anilines to form a series of allylic amines, which have been reported to be important structures of many bioactive molecules. And the reaction afforded high yields and finished in a short time under very mild conditions.Last, we have developed an efficient cross-coupling reaction between propargyl compounds and alcohols/phenols/acids to form C-O bonds via Sp C-H bond activation promoted by DDQ. This provides a wide scope of propargyl ethers/esters and propargyl ketals, which can serve as substrates or intermediates in countless transformations, especially in the synthesis of allenes.