Palladium/Copper-Catalyzed Denitrogenative Alkylidenation and ortho-Alkynylation Reaction of 1,2,3-Benzotriazin-4(3H)-ones.

An efficient palladium-catalyzed approach to access various functionalized (Z)-3-benzylidene-isoindoline-1-ones and (Z)-3-benzylidene(imino)isobenzofuranones via a denitrogenative tandem alkynylation/cyclization reaction of 1,2,3-benzotriazin-4(3H)-ones with aromatic terminal alkynes is described. Furthermore, a denitrogenative ortho-alkynylation reaction of 1,2,3-benzotriazinones with aliphatic terminal alkynes is also developed. The reaction proceeds through a five-membered azapalladacyclic intermediate with the extrusion of a nitrogen molecule. The significance of the reaction is also demonstrated by a one-pot synthesis of (Z)-3-benzylideneisobenzofuran-1(3H)-one derivatives in good to high yields.

Nickel-Catalyzed Denitrogenative Cross-Coupling Reaction of 1,2,3-Benzotriazin-4(3 H)-ones with Organoboronic Acids: An Easy Access to Ortho-Arylated and Alkenylated Benzamides.

A novel nickel-catalyzed approach to synthesize ortho-arylated and alkenylated benzamides in good to high yields via a denitrogenative cross-coupling reaction of 1,2,3-benzotriazin-4(3 H)-ones with organoboronic acids is described. The reaction proceeds through a five-membered azanickelacyclic intermediate with the extrusion of a nitrogen molecule. Moreover, the resulting ortho-arylated benzamides were successfully converted into synthetically useful substituted fluorenones and ortho-arylated benzylamine derivatives in high yields.