Tandem Fluorination Ritter-type Reaction And N-H Insertion Study Based On The 3-diazo-2H-benzopyran-4-one

This thesis consists of three sections.The first section introduces fluorination,Ritter reaction in the form of reviews.According to the type of fluoride reagents,electrophilic fluorination,nucleophilic fluorination,radical fluorination and their corresponding mechanism are described respectively;the developments of Ritter reaction and its mechanism are also described in detail.Additionally the metal carbenoids derived from diazo compound and its classical insertion reaction including X-H(including the C-H,O-H,N-H,S-H)are also reviewed,especially in the form of Rhodium carbenoids catalyzed N-H insertion to synthesize hydrozone-type compounds.The second and third sections are core of my thesis.The methodology studies based on 3-diazo-2H-benzopyran-4-one substrates are mainly described.The experiment works were carried out in two patrts: firstly we developed tandem fluorination Ritter-type reaction to build fluorinated quaternary carbon center and amide derivatives of 2H-benzopyran-4-one in one-step.This method is new and effective in the synthesis of fluorinated amide derivatives based on 2H-benzopyran-4-one skeleton.Fluorinated benzofuranone is the key motif of many natural products,and we hope to finish the total synthesis of similar natural products by using this new method.Secondly we accomplished N-H insertion of diazo motif to sp3 C-H to construct C-N bond in the synthesis of hydrozone-type compounds of 2H-benzopyran-4-one.Using diazo motif to construct hydrozone-type compounds of 2H-benzopyran-4-one is also of novelty.