화학공학소재연구정보센터
Inorganic Chemistry, Vol.56, No.24, 15110-15118, 2017
Tunable Emission of Iridium(III) Complexes Bearing Sulfur-Bridged Dipyridyl Ligands
A series of six new cyclometalated iridium(III) complexes [Ir(ppy)(2)(N boolean AND N)][PF6] (ppy = 2-phenylpyridine) is reported herein. Proligands bis(pyridin-2-yl)sulfane (1a), 2,2'-sulfinyldipyridine (1b), 2,2'-sulfonyldipyridine (1c), bis(4-methylpyridin-2-yl)sulfane (2a), 2,2'-sulfinylbis(4-methylpyridine) (2b), and 2,2'-sulfonylbis(4-methylpyridine) (2c) were synthesized, characterized, and employed as the NAN ancillary ligand. Changing the oxidation state of the sulfur atom serves as a switch to alter the emissive state from that of mainly (LC)-L-3 character (blue-green emission) to one of (MLCT)-M-3/(LLCT)-L-3 character (yellow emission). Sulfide and sulfoxide complexes Ir(la), Ir(lb), Ir(2a), and Ir(2b) show identical, vibrationally structured emission profiles with maxima at 478, 510, 548 nm in CH2Cl2 solutions resulting from a (LC)-L-3 state.