Study On Organic Reactions Involving Aromatic Triazenes As The Arylation Reagents

Aromatic triazenes, which are very useful and versatile intermediates inorganic synthesis, can be readily prepared from the corresponding arylamines by meansof a simple one-step procedure. Transition-metal-catalyzed organic reactions havereceived much attention and emerged as one of the most significant strategies in modernorganic synthesis for its peculiarities of simplified procedure, environmental friendly andhigh atom efficiency compared with traditional method. Usually，transition metal includeruthenium, rhodiun, palladium, nickel, copper, silver, gold and so on. Among them,palladium and rhodiun are absolutely essential ones in organic synthesis, and palladiumand rhodiun-catalyzed cross-coupling reactions have been widely and thoroughlyinvestigated. In this paper, we have mainly studied the palladium catalyzed direct C-2arylation of1-aryltriazenes with N-substituted indoles and azoles, and the Rh-catalyzedcyclization reaction of1-aryltriazenes with N-methoxybenzamides.The thesis consists of the following three parts:1. Pd-catalyzed direct C-2arylation of1-aryltriazenes with N-substituted indoles to2-arylindoles. In the presence of BF3·OEt2and Pd(OAc)2, N-substituted indoles reactedwith1-aryltriazenes in DMAC to afford the corresponding aryl–indole type products ingood to excellent yields.2. Pd-catalyzed direct C-2arylation of1-aryltriazenes with azoles to2-arylsubstituted azoles. Azoles including oxazoles, thiazoles, imidazoles,1,3,4-oxadiazoles, and oxazoline could react with1-aryltriazenes smoothly to generatethe corresponding products in good to excellent yields, and various substitution patternswere tolerated toward the reaction.3. Rh-catalyzed multiple steps C H activation of1-aryltriazenes withN-methoxybenzamides to phenanthridinones. The reactions underwent smoothly at roomtemperature to generate the corresponding products in good to excellent yields throughan arylation-amination process. This method is an newly and efficiency access for theconstruction of substituted phenanthridinon.