title: Emissive iridium(III) diimine complexes formed by double cyclometalation of coordinated triphenylphosphite.
abstract: We report on the synthesis of a new series of iridium(III) complexes functionalized with various diimine chromophores, together with a facially coordinated dicyclometalated phosphite chelate and a monodentate anionic ancillary. This conceptual design presents a novel strategy in obtaining a new class of iridium(III) diimine complexes without employment of traditional nitrogen-containing polyaromatic cyclometalates. Additionally, we discuss the basic charactersistics of the ground and lower-lying excited states involved, as documented by crystal structural, photophysical studies, and density functional theory calculations. Fabrication of the green-emitting organic light-emitting diodes with one such dopant, [Ir(dbbpy)(tpit)NCS] (2b), where dbbpy and tpit represent di-tert-butyl-2,2'-bipyridine and dicyclometalated triphenylphosphite, respectively, was successfully made, attaining a peak external quantum efficiency (η(ext)), a luminance efficiency (η(l)), and a power efficiency (η(p)) of 14.1%, 46.6 cd A(-1), and 39.9 lm W(-1), respectively.
authors.affiliation: Department of Chemistry, National Tsing Hua University, Hsinchu 30013, Taiwan.
authors.forename: Yao-Yuan
authors.initials: YY
authors.lastname: Chang
authors.forename: Jui-Yi
authors.initials: JY
authors.lastname: Hung
authors.forename: Yun
authors.initials: Y
authors.lastname: Chi
authors.forename: Jong-Pyng
authors.initials: JP
authors.lastname: Chyn
authors.forename: Min-Wen
authors.initials: MW
authors.lastname: Chung
authors.forename: Chia-Li
authors.initials: CL
authors.lastname: Lin
authors.forename: Pi-Tai
authors.initials: PT
authors.lastname: Chou
authors.forename: Gene-Hsiang
authors.initials: GH
authors.lastname: Lee
authors.forename: Chih-Hao
authors.initials: CH
authors.lastname: Chang
authors.forename: Wei-Chieh
authors.initials: WC
authors.lastname: Lin