We report a new approach for a highly regioselective synthesis of isoquinolones from various substituted benzamides and alkynes.

The synthesis of phenanthridinones via denitrogenative annulation of 1,2,3‐benzotriazin‐4‐(3H)‐ones with arynes catalysed by Ni(0)/dppm was successfully developed. A variety of phenanthridinones were prepared in good to excellent yields. Based on this method, nature product, N‐methylcrinasidine, was synthesized.magnified image

Denitrogenative ortho-arylation, vinylation and methylation of 1,2,3-benzotriazin-4-(3H)-ones with organic boronic acids catalyzed by nickel complexes to give a wide range of o-substituted benzamides were demonstrated. Further, the catalytic reaction is successfully applied to the synthesis of the popular hypertensive drugs losartan and irbesartan in high yields.

The Co-catalyzed reactions of 2-halobenzamides and alkynes to form isoquinolones or 2-vinyl benzamides are described. Formation of the two selective products can be fully controlled by adopted ligands. Study of...

Herein, we report the nickel-catalyzed denitrogenative cyclization reaction of 1,2,3,4-benzothiatriazine-1,1-dioxides with arynes to generate the polysubstituted biaryl sultams with tolerance of a wide diversity of substituents on every subunit. The mechanistic study indicates that the reaction is initiated by the formation of a diradical species, which reacts with a nickel complex to form a nickelacycle intermediate and carries out the subsequent cyclization through insertion of an aryne.