A compound of Formula I, is provided. In Formula I, one of Z1, Z2, and Z3 is N and the remainder are C; each of L1 and L2 is independently selected from a direct bond and a linking group; at least one of R1, R2, RA, RB, RC, RD, and RE comprises a group R* having a structure selected form the group consisting of Formula II, -Q(R3)(R4)a(R5)b, Formula III, and Formula IV, Each R, R′, R″, R1, R2, R3, R4, R5, RA, RB, RC, RD, RE, RF, RG, and RH is independently hydrogen or a General Substituent, with the proviso that group R* is not adamantyl. Formulations, OLEDs, and consumer products containing the compound are also provided.