Copper-Catalyzed Nitrogen Atom Transfer to Isoquinolines via C-N Triple Bond Cleavage and Three-Component Cyclization

Electrochemically Driven Chalcogenative Cyclization of 2-Alkynyl Aryl Oxime: Access to Functionalized Isoquinolines

A transition-metal-free electrochemical chalcogenative cyclization of 2-alkynyl aryl oxime with dichalcogenides has been established to assemble valuable 4-organochalcogen isoquinolines concisely. This protocol proceeds via constant electrolysis in a user-friendly undivided cell setup. It circumvents the necessity of transition metal catalysts, chemical oxidants, and harsh reaction conditions. The practical utilities of the current protocol were illustrated by excellent functional group tolerance, remarkable regio-selectivity, easy scalability, mild reaction conditions, and transformable 4-organochalcogen isoquinoline products.

A Cascade Synthesis of Furo-Pyrrolo-Pyridines via Pd(II)-Catalyzed Dual N-H/C Annulative-Cyclization

A Pd(II)-catalyzed non-template synthesis of furo[2,3-b]pyrrolo[2,3-d]pyridines from β-ketodinitriles and buta-1,3-diynes has been accomplished via dual annulative cyclization. The participation of both the nitrile (-CN) groups led to the concurrent construction of three heterocycles viz. furan, pyrrole, and pyridine forming C-C, C=C, C-O, C-N, and C=N bonds in one pot. The synthetic utility of the protocol was further demonstrated through a few post-synthetic manipulations.