Copper complexes for the chemoselective N -arylation of arylamines and sulfanilamides via Chan–Evans–Lam cross-coupling

Copper( ii ) complexes with tridentate NNN -ligands were utilized for Chan–Evans–Lam (CEL) cross-coupling reactions to enable the N -arylation of multifarious N -nucleophiles through the activation of aryl boronic acids. A condition-specific methodology was developed to chemoselectively target the amine versus sulfonamide N -arylation of 4-aminobenzenesulfonamide using new catalysts. Two different pyridine-based ligands and corresponding copper( ii ) complexes were characterized using 1 H and 13 C-NMR, FTIR, and UV-vis spectroscopy, HRMS, single-crystal X-ray diffraction, and cyclic voltammetry. Solvent and base-controlled cross-coupling reactions were observed, which led to the optimization of selective conditions for targeted C–N bond formation of sulfanilamides. Beyond the chemoselective processes reported here, a breadth of N -nucleophiles including sulfanilamides and arylamines were screened for arylation by this CEL catalyst.