Triphenylsilyl- and trityl-substituted carbazole-based host materials for blue electrophosphorescence.

Carbazole-based materials adopting the nonconjugated substitution of triphenylsilyl (-SiPh(3)) and trityl (-CPh(3)) side groups are studied as high-triplet-energy, morphologically, and electrochemically stable host materials with tunable carrier-transport properties for organic blue electrophosphorescence. The developed host materials 9-(4-tert-butylphenyl)-3,6-bis(triphenylsilyl)-9H-carbazole (CzSi), 9-(4-tert-butylphenyl)-3,6-ditrityl-9H-carbazole (CzC), and 9-(4-tert-butylphenyl)-3-(triphenylsilyl)-6-trityl-9H-carbazole (CzCSi) all show high triplet energies of 2.97-3.

Versatile one-step introduction of multiple hydrogen-bonding sites onto extended pi-conjugated systems.

Unprotected arylbiuret units were smoothly introduced onto pi-conjugated structures to afford new supramolecular materials leading to interpenetrated networks.

Solid-state white light-emitting electrochemical cells using iridium-based cationic transition metal complexes.

White electroluminescent (EL) emission from single-layered solid-state light-emitting electrochemical cells (LECs) based on host-guest cationic iridium complexes has been successfully demonstrated. The devices show white EL spectra (Commission Internationale de l'Eclairage coordinates ranging from (x, y) = (0.45, 0.

Novel spiro-configured PET chromophores incorporating 4,5-diazafluorene moiety as an electron acceptor.

[reaction: see text] We have synthesized novel spiro-bridged chromophores incorporating a 4,5-diazafluorene unit as the electron acceptor (A) and aryl amino groups as donor (D) moieties. The orthogonal D-A configuration limits ground-state D-A interactions but allows efficient PET reactions. The PET efficiency was modulated by the electronic characteristics of the donor and by the D-A distance.

Modulation of physical properties of Ter(9,9-ditolylfluorene) by backbone-embedded heteroarenes.

[structure: see text] Novel ter(9,9-ditolylfluorene) analogues containing thiophene and pyridine rings embedded as functional constituents within the parent hydrocarbon backbone have been synthesized. These new molecules exhibit highly efficient photoluminescence and high thermal and morphological stability. The electronic structure of the terfluorene backbone is significantly perturbed, which allows modulation of the backbone energy levels.

4,5-Diazafluorene-incorporated ter(9,9-diarylfluorene): a novel molecular doping strategy for improving the electron injection property of a highly efficient OLED blue emitter.

A more efficient OLED device with blue emission characteristic of terfluorene has been achieved by using a novel molecular doping strategy, in which 4,5-diazafluorene was incorporated as the substitution group of terfluorene to facilitate electron injection from the metal cathode yet without altering emission characteristics.

A new series of pyrimidine-containing linear molecules: their elegant crystal structures and intriguing photophysical properties.

A new series of aza-substituted analogues 3-5 based on the 1,4-bis(phenylethynyl)benzene moiety have been synthesized by the selective Pd-catalyzed Sonogashira coupling reaction from 5-bromo-2-iodopyrimidine (1). In these linear molecules, the dipolar pyrimidine moiety is introduced as a probe to investigate factors that control the intermolecular interactions over the crystal engineering. The results reveal that the manner of packing changes both dipolar interactions between linear pyrimidine-containing molecules and transition moments simultaneously, resulting in remarkably different photophysical properties.