Selective photooxidation of sulfides catalyzed by bis‐cyclometalated IrIII photosensitizers bearing 2,2′‐dipyridylamine‐based ligands

Abstract

A new family of heteroleptic bis-cyclometalated IrIII complexes with formula [Ir(C _ N)2(N _ N)]Cl (C _ N=2-phenylpyridinate and N _ N=2,2’-dipyridylamine or N-benzylated 2,2’-dipyridylamines, were synthesized, characterized, and successfully used as photosensitizers in the catalytic photooxidation of an array of dialkyl, dibenzyl, alkyl aryl, and diaryl sulfides, as well as sulfur-containing amino acids. Furthermore, the reactions proceeded with optimal chemoselectivity, and atom economy under mild conditions. Experimental observations support a dual mechanism in which singlet oxygen and superoxide are the actual oxidants.