Atom-Economical Synthesis of Unsymmetrical Diaryl Selenides from Arylhydrazines and Diaryl Diselenides

摘要

An atom-economical method for the synthesis of unsymmetrical diaryl selenides from arylhydrazines and stoichiometric amounts of diselenides was developed under mild conditions. The new and facile selenide synthesis involved the use of an inexpensive base in air to form unsymmetrical diaryl selenides in good yields. This C–Se radical arylation of diaryl diselenides was performed by forming aryl radicals from arylhydrazines under oxidative conditions. The formation of a phenyl radical was supported by trapping with 2,2,6,6-tetramethylpiperidine-1-oxyl (TEMPO) in air. Therefore, this synthesis might involve a homolytic aromatic substitution (HAS) mechanism. The synthesis is both low costing and environmentally friendly and, therefore, may be useful for the practical synthesis of unsymmetrical diaryl selenides.