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With the development of ortho C-H functionalization in Pd/NBE chemistry, the catalytic systems used are becoming increasingly complex. The increasingly complex catalytic systems may have created technical barri-ers for researchers in other fields to apply Pd/NBE chemical methods. This report describes the use of a simple Pd/NBE catalytic system to achieve ortho C-H oxylation and phosphonylation and other functionalization of iodobenzene through templated conversion reactions. The key point of this method is to explore the previous-ly unknown step of introducing dimethylamine in the ortho position of iodobenzene through C-H amination. Aryl dimethylamine is quickly converted to methyl quaternary ammonium salt precipitation, and methyl qua-ternary ammonium salt effectively avoids Hofmann elimination in the subsequent functionalization.

In palladium/norbornene (Pd/NBE) chemistry, the "ortho effect" has been proven to be a key factor in the process of β-carbon elimination to extrude NBE. Herein, we found that the o-iodoaniline protected by a p-methoxybenzenesulfonyl group can recover the "ortho effect" and then undergo N-S bond cleavage with vinyl palladium, thus achieving a highly selective C-N coupling reaction in the Catallani-Lautens reaction system. On the basis of this discovery, a one-step synthesis of highly functionalized tricyclic indole derivatives was realized.

The free radical cyclization reaction is a promising strategy for ring framework formation. Herein, we report a copper-catalyzed tandem radical cyclization strategy for preparing substituted lactam derivatives. This reaction proceeds through a radical coupling approach, which not only allows a wide range of alkenes but also is quite compatible with the primary, secondary, and tertiary radicals. In addition, density functional theory calculations were performed to gain insights into the reaction mechanism.