Bis(2‐pyridinyl)‐oxalamide copper complexes: Scope and limitation in CuAAC and oxidative hydroxylation of arylboronic acids

Abstract

AbstractA versatile catalytic platform consisting of pyridine‐containing oxalamide and copper salt was developed. The resulting complexes were fully characterized by spectroscopic analyses, showing a successful complexation of copper metal. The applicability of the newly prepared platforms was evaluated in a one‐pot three‐components system for the preparation of 1,4‐disubstituted 1,2,3‐triazole via 1,3‐dipolar cycloaddition of terminal acetylenes, benzyl surrogates, and sodium azide in an aqueous environment. The corresponding cyclization proceeded smoothly affording the expected triazole products in moderate to good yields. In addition, the transformation of arylboronic acids to the corresponding phenols via ipso‐hydroxylation was also explored using the same platform in an aqueous basic condition. In the course of the study, unfortunately, some drawbacks that could limit the applicability of the catalytic platform were also observed especially in terms of recyclability of the platforms.