Cross-electrophile coupling of triazine esters with aryl bromides could be facilely accomplished by employing nickel as catalyst,magnesium as metal mediator,and lithium chloride as additive.The reactions proceeded eff...Cross-electrophile coupling of triazine esters with aryl bromides could be facilely accomplished by employing nickel as catalyst,magnesium as metal mediator,and lithium chloride as additive.The reactions proceeded efficiently in THF at room temperature through C—O bond activation to afford an array of structurally different diaryl ketones in moderate to good yields with wide functional group tolerance.Control experiments showed that nickel,magnesium,lithium chloride,and THF are all indispensable for the good performance of the coupling reaction.Preliminary mechanistic exploration indicated that in situ formed arylmagnesium reagent by the insertion of magnesium into aryl bromide might serve as the key intermediate of the cross-coupling.The method which avoids the utilization of moisture-labile and relatively difficult-to-obtain organometallics is step-economical,cost-efficient,and operationally simple,potentially serving as an attractive alternative to documented methods.展开更多
基金the financial support from Nanjing Tech University(Start-up Grant Nos.39837118 and 39837146)National Natural Science Foundation of China(22271062,22001121,and 22171137)+1 种基金Natural Science Foundation of Jiangsu Province(BK20180690)X.-Q.Chu is grateful for the financial support from the program of China Scholarship Council(No.201908320190).
文摘Cross-electrophile coupling of triazine esters with aryl bromides could be facilely accomplished by employing nickel as catalyst,magnesium as metal mediator,and lithium chloride as additive.The reactions proceeded efficiently in THF at room temperature through C—O bond activation to afford an array of structurally different diaryl ketones in moderate to good yields with wide functional group tolerance.Control experiments showed that nickel,magnesium,lithium chloride,and THF are all indispensable for the good performance of the coupling reaction.Preliminary mechanistic exploration indicated that in situ formed arylmagnesium reagent by the insertion of magnesium into aryl bromide might serve as the key intermediate of the cross-coupling.The method which avoids the utilization of moisture-labile and relatively difficult-to-obtain organometallics is step-economical,cost-efficient,and operationally simple,potentially serving as an attractive alternative to documented methods.
