Synthesis Of C-C Bond Via Activation Of C-H Bond With Transition Metals Catalyst Rh,Ag,Fe

Transition metal catalyzed C-H bond functionalization not only can effectively shorten the reaction step,but also has high atomic economy,so it is one of the most important research directions of organic synthesis methodology.Therefore,the development of a new C-H bond activation strategy to directly construct important organic small molecule skeletons has potential industrial application value.In this thesis,three different transition metal catalyst systems have been developed to realize different types of C-C bonding reaction,and to synthesize different types of skeletons in natural products,bioactive molecules and drug molecules.The types of reactions involved include oxidative coupling,benzylation and di:fluoromethylation.First,we developed a ruthenium-catalyzed oxidative coupling reaction of acrylic acid with an alkyne to form a natural product or a core skeleton commonly found in biologically active intermediates,a-pyrone.This strategy greatly improves the functional group compatibility of such reactions and provides an efficient strategy for the synthesis of these compounds.Secondly,we have developed a silver-catalyzed benzylation reaction of acetanilide,providing a simple and practical strategy for the synthesis of various triphenylmethane compounds.Such molecules often consist in organic dyes,supramolecular structures and the core skeleton of drugs.This strategy has potential application prospects.Finally,we use low-cost iron as a catalyst to solve the difficult problem of uncontrollable site selectivity of arylaldehydes.It is the first time to achieve the para-selective fluoromethylation of arylaldehydes.It provides a simple method for the discovery of prodrags and the development of new drugs.Three synthetic strategies above are based on the transition metal-catalyzed synthesis of C-C bonds,and make a uaique contribution to broadening the type of transition metal-catalyzed coupling reaction.All products are identified by 1H NMR,13C NMR,partially 19F NMR and HRMS.