| abstract |
There is disclosed a compound having Formula IIn Formula, I: Ar1 is selected from the group consisting of dibenzofuran, dibenzothiophene, or deuterated analogs thereof; Ar2 and Ar3 are the same or different and are hydrocarbon aryl, substituted derivatives thereof, or deuterated analogs thereof, with the proviso that Ar2 and Ar3 are not the same as Ar1; a is 0; and Ar1, Ar2, and Ar3 have no additional amino substituents. |