Researches On The Formation Of C-O Bond Via The Oxidative C-H Activation

C-H bond activation reactions are challenging topic in modem synthetic chemistry. C-C and carbon-heteroatom bonds can be readily formed through C-H bond activation reactions.C-H bond activation reactions catalyzed by transition metals can be used to shorten the reaction steps and improve the atom economy.It is a convenient synthetic method which has been widespread investigated by chemists. Oxidative C-H bond activation reaction can also be used to build C-X(X=C,O,N,S, etc.) with or without metal catalyst under mild condition.The researches possess great meaning from both economic and environmental points of view.This dissertation is consisted of three chapters.The first chapter is a review to summarize the C-H bond activation reactions.Both transition-metal catalyzed C-H bond activation reactions and oxidative C-H bond activation reactions were introduced.In particular,total overview of sp³ oxidative C-H bond activation reaction had been done.In the second part of this dissertation,the C-H activation of cyclohexane mediated by PhI(OAc)₂/CuCl is discussed.The cross-coupling between cyclohexane and N-hydroxyphthalimide(NHPI) was happened in mild condition using cyclohexane and NHPI as the strarting materials.The saturated sp³ C-H bond activation was achieved and new C-O bond was formed without any active functional groups.In the third part of this dissertation,we studied DDQ promoted cross dehydrogenative coupling of allyl compounds with oxime through C-H bond activation.The DDQ promoted coupling of 1,3-diphenylpropene with aliphatic and aromatic oxime were performed in CH₂Cl₂.This reaction can proceed easily in shorter time with a high yield even at the room temperature.We further investigated the reaction between 3-methyl-1-phenylbut-1-ene and oxime.To our delight,oximes containing an electron-rich group reacted rapidly and higher stereoselectively.