| 摘要 |
A compound of formula (I) wherein: Ar1 represents an aryl or heteroaryl group that may be unsubstituted or substituted with one or more substituents; n is 0 or 1; and Xan independently in each occurrence represents a group selected from formula (IIa) or (IIb): wherein X is O or S; R1 independently in each occurrence is H or a substituent; R2 independently in each occurrence is H or a substituent; p independently in each occurrence is 0, 1, 2, 3 or 4; q is 0, 1, 2 or 3; and * represents a bond to Ar1. Use of compounds of formula (I) as a host for phosphorescent emitters is disclosed. |
