| abstract |
Disclosed are compounds having the structure of Formula I: In structure I: X is selected from the group consisting of O, S and Se; G 2 and G 3 are benzene, biphenyl, fluorene, naphthalene, phenanthrene, triphenylene, dibenzofuran, dibenzothiophene, dibenzoselenophene, pyridine, pyrimidine, quinoline, isoquinoline, phenanthrole, respectively. independently selected from the group consisting of phosphorus, aza-fluorene, and combinations thereof; L is selected from phenyl, biphenyl, terphenyl and pyridine, and combinations thereof; G 2 , G 3 and L are each optionally further substituted with one or more non-fused substituents; R 1 , R 2 , and each of R 3 , R 4 , R 5 and R 6 are hydrogen, deuterium, alkyl, alkoxyl, cycloalkyl, cycloalkoxyl, halogen, nitro, nitrile, silyl, benzene, biphenyl, a non-fused substituent selected from terphenyl, pyridine, and combinations thereof; R 1 and R 2 are optionally linked to form a ring. Formulations and devices, such as OLEDs, comprising a compound of formula I and, optionally, an auxiliary host are also described. |