Visible-light-promoted O-H Insertion And Phosphorylation Of Diazo Compounds

The visible-light-promoted reaction is favored because of its mild reaction conditions,sustainability,high efficiency,and good selectivity.Due to its excited state chemistry characteristics and unique catalytic reaction mode,it shows unique advantages in organic transformation and has become one of the hotspots of organic synthetic chemistry.Diazo compounds are easy to prepare,have active chemical properties,and participate in various organic transformations.They are important synthetic intermediates in organic synthesis and key components of many synthetic transformations.They are widely used in organic synthesis,chemical biology,materials chemistry,medicinal chemistry,and other fields.In recent years,visible-light-promoted reactions involving diazonium have received extensive attention from chemists,and even without the need to add photocatalysts,such as X-H insertion,cycloaddition,and coupling reactions can be achieved.However,the visible-light-promoted selective O-H insertion of diazo compounds into 2-pyridone and the phosphorylation reaction with P(O)H compounds have not been reported yet.In view of these,based on the full investigation of the literature,aiming to the research status and deficiencies of the selective O-H insertion of diazo compounds with 2-pyridone and the phosphination reaction with P(O)H compounds,this thesis will study the visible-light-promoted O-H insertion and phosphorylation reactions of diazo compounds,with a view to establishing new methods for the corresponding reactions.The main research contents of the thesis include the following two parts Part Ⅰ:Visible-light-promoted selective O-alkylation of 2-pyridones withα-diazoesterWe have developed a visible-light-promoted method for the O-H insertion reaction of α-aryldiazoacetate with 2-pyridone.Without using any catalysts and additives,the selective O-alkylation of 2-pyridone has been realized under mild conditions by direct blue light irradiation.A variety of 2-pyridones andα-aryldiazoacetates reacted smoothly,and the O-alkylated products were obtained with excellent selectivity.Different from the previously reported metal-catalyzed reactions,the free radical reaction pathway may be the key to the good chemical selectivity of this protocol,providing a new access for the O-H insertion reaction.Part Ⅱ:Visible-light-promoted phosphorylation reaction from α-diazoester and P(O)H compoundsWe have developed a visible-light-promoted phosphorylation reaction ofα-diazoesters and P(O)H compounds.Upon direct blue light irradiation and in the presence of 50 mol%DBU,the phosphorylation of α-diazoesters has been realized under mild conditions.The experimental studies showed that visible light promoted the reaction significantly.A range of α-diazoesters and P(O)H compounds reacted smoothly under the optimal conditions,affording the target products in high yields.The established protocol provides a novel,mild and efficient approach for the synthesis of phosphorus-containing organic compounds.