Synthesis of -arylated and alkenylated benzamides by palladium-catalyzed denitrogenative cross-coupling reactions of 1,2,3-benzotriazin-4(3)-ones with organoboronic acids

• Published in: New journal of chemistry 2021-09, Vol.45 (37), p.1719-17195
• Main Authors: Balakrishnan, Madasamy Hari, Kanagaraj, Madasamy, Sankar, Velayudham, Ravva, Mahesh Kumar, Mannathan, Subramaniyan
• Format: Article
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/d1nj03706d

An efficient palladium-catalyzed denitrogenative Suzuki-Miyaura type cross-coupling of 1,2,3-benzotriazin-4(3 H )-ones with organoboronic acid is described. The reaction is compatible with various aryl and alkenyl boronic acids affording ortho -arylated and alkenylated benzamides in good to high yields. Heteroaromatic boronic acids were also successfully employed. Along with this, a coupling reaction was established by using phenyl boronate ester as the coupling partner. The reaction is believed to proceed via a five-membered aza-palladacyclic intermediate. DFT calculations were studied comparing the reactivity of palladium and nickel complexes in the five-membered aza-metallacycle formation from 1,2,3-benzotriazin-4(3 H )-ones. The application of the reaction was successfully demonstrated by converting ortho -alkenylated products to ortho -alkylated products in high yields via a reduction reaction. An efficient palladium-catalyzed denitrogenative cross-coupling reaction of 1,2,3-benzotriazin-4(3 H )-ones with organoboronic acids is described. The reaction affords various ortho -aryl and alkenylated benzamides in good to high yields.