A Highly Efficient And Stable Diazo-Transfer Reagent For Fast Synthesis Of Diazo Compounds

In organic synthesis chemistry,diazo compounds as carbenes and metal carbenes precursors are very valuable building blocks.Diazo compounds catalyzed by transition metal(rhodium,copper,palladium,iron,ruthenium,indium,cobalt,etc.)in situ generate metal carbenes,which can perform an array of reactions with a remarkable degree of chemo-,regio-,and stereoselectivity,such as X-H(X = C,Si,N,0,S,B)insertion reaction,olefin cyclopropanation,cyclopropenylation of acetylene,and formation of ylide.Diazo transfer reaction is one of the effective methods for preparing diazo compounds.The diazo transfer reagents reported in the previous literature are still not ideal.Some reagents have the potential hazard of explosion.Most of them cannot be stored for a long time and the use conditions are harsh.Therefore,it is necessary to develop safe,stable,and efficient diazo transfer reagents.In the first part of the thesis,we summarizes the main routes for preparing diazo compounds,and describes the application of transition metal catalyzed diazo compounds in the organic synthesis.In the second part,we describe our research in detail.We have developed a highly efficient and safe crystalline solid reagent ADT for diazo-transfer reaction of activate methylene compounds.ADT can be facilely synthesized from low-cost and convenient starting materials.ADT shows good thermal stability,insensitivity to shock or friction,and great stability upon long-term storage.With inorganic solid base as catalyst,the diazo-transfer reaction based on ADT gives various diazo compounds in excellent yields within several minutes at room temperature,making ADT a promising diazo-transfer reagent for quick preparation of diazo compounds.In the third part of the thesis,the reaction of ADT and some activated methylene compounds was performed in a mixed solvent of water and dimethyl sulfoxide.Only triazole products were formed with high yields.We proposed a mechanism to explain this solvent-controlled reaction.In the fourth part of the thesis,the copper-catalyzed allenylic silanes were prepared under mild conditions.We proposed a possible reaction mechanism.