The origin of regioselectivity in meta-selective C-H borylation of benzamides directed by hydrogen bond interaction between ligand and substrate is elucidated through combined computational and experimental studies.We...The origin of regioselectivity in meta-selective C-H borylation of benzamides directed by hydrogen bond interaction between ligand and substrate is elucidated through combined computational and experimental studies.We discover that a non-directed pathway,in which the urea moiety in ligand recognizes the O atom in Bpin instead of substrate,competes with the directed pathway and erodes the meta-selectivity.The non-directed pathway is sensitive to steric repulsion between Bpin and urea,and thus can be impeded by introducing a bulky substituent into the urea moiety.Accordingly,we optimize the ligand and improve the meta-selectivity in the Ir-catalyzed C-H borylation of some previously reported unsuccessful arenes.展开更多
An electron-deficient[CpERhCl2]2 catalyzed annulation of N-pentafluorophenylbenzamides with internal alkynes was successfully established under mild reaction conditions,with the assistance of Lewis acid silver salt.Pa...An electron-deficient[CpERhCl2]2 catalyzed annulation of N-pentafluorophenylbenzamides with internal alkynes was successfully established under mild reaction conditions,with the assistance of Lewis acid silver salt.Particularly,electron-deficient benzamide substrates were smoothly transformed into the desired products in this catalytic system.The catalytic system showed a broad tolerance for different substituents on the aromatic rings or aryl,alkyl-substituted alkynes.展开更多
基金financial support from the Fundamental Research Funds for the Central Universities(Nos.020514380253,020514380277)the Natural Science Foundation of Jiangsu Province(No.BK20211555)the Jiangsu Innovation&Entrepreneurship Talents Plan。
文摘The origin of regioselectivity in meta-selective C-H borylation of benzamides directed by hydrogen bond interaction between ligand and substrate is elucidated through combined computational and experimental studies.We discover that a non-directed pathway,in which the urea moiety in ligand recognizes the O atom in Bpin instead of substrate,competes with the directed pathway and erodes the meta-selectivity.The non-directed pathway is sensitive to steric repulsion between Bpin and urea,and thus can be impeded by introducing a bulky substituent into the urea moiety.Accordingly,we optimize the ligand and improve the meta-selectivity in the Ir-catalyzed C-H borylation of some previously reported unsuccessful arenes.
基金We gratefully acknowledge the National Natural Science Foundation of China(Nos.21671097 and 21573106)the Fundamental Research Funds for the Central Universities for financial support.
文摘An electron-deficient[CpERhCl2]2 catalyzed annulation of N-pentafluorophenylbenzamides with internal alkynes was successfully established under mild reaction conditions,with the assistance of Lewis acid silver salt.Particularly,electron-deficient benzamide substrates were smoothly transformed into the desired products in this catalytic system.The catalytic system showed a broad tolerance for different substituents on the aromatic rings or aryl,alkyl-substituted alkynes.
