A compound of Formula I wherein X1, X2, X3, and X4 are independently selected from the group consisting of CRA and N; X5, X6, X7, and X8 are independently selected from the group consisting of CRB and N; Y is selected from the group consisting of NR2, O, S, CR3R4, SiR3R4 and GeR3R4; Z is selected from the group consisting of B, SiR5, and GeR6; wherein RA and RB represent mono to the maximum allowable substitution, or no substitution; and R1, R2, R3, R4, R5, R6 and R7 are independently selected from the group consisting of hydrogen, deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, arylalkyl, alkoxy, aryloxy, silyl, aryl, heteroaryl, acyl, nitrile, and combinations thereof. The compounds of Formula I will have at least one of RA, RB, R1, R2, R3, R4, R5 and R6 that comprises a structure selected from the group consisting of: wherein X is selected from the group consisting of NR7, O, S and Se; and X9-X41 are each independently selected from the group consisting of C and N; and at least one of X34-X41 is N. We also describe an OLED comprising an organic layer that includes a compound of Formula I and a consumer product that includes the OLED.