Organic electroluminescent materials and devices

An organic light emitting device (OLED) comprising:

• an anode;
• a cathode;
• and
• an organic layer disposed between the anode and the cathode,
• wherein the organic layer comprises a compound having a structure of Formula I:
• wherein:
• each of R1 to R7 is independently a hydrogen or a substituent selected from the group consisting of phenyl, and a system consisting of two to ten phenyl groups connected to each other;
• at least two of R1 to R7 are not hydrogen;
• if R1 and R3 are not hydrogen, then at least one of the following is true:
• 1) R1 and R3 are different from each other;
• or 2) at least one of R1 or R3 is an unsubstituted phenyl;
• if one of the at least two R1 to R7 that is not hydrogen is the system consisting of two to ten phenyl groups connected to each other, then the phenyl group directly bonded to the structure of Formula I having X bonds to exactly one phenyl group;
• R8 and R9 are each independently selected from the group consisting of phenyl, and a system consisting of two to ten phenyl groups connected to each other;
• X is selected from the group consisting of O, S, and Se;
• and
• L is selected from the group consisting of direct bond and
• wherein m is an integer from 1 to 5, and RA is a hydrogen or a substituent selected from the group consisting of aromatic and heteroaromatic rings;
• and
• subject to the following provisos i) to iv):
• i) if L is biphenyl, one phenyl of the biphenyl bonds to ring A and the other phenyl bonds to ring B;
• ii) if X is O, then least one of R1, R3, or R5 is H;
• iii) if X is S, then at least one of R1 or R6 is H but if R6 is H and R1 is not H, then at least one of R3 or R5 is H;
• and
• iv) the following structures are excluded
• and
• wherein at least one of the following conditions 1) to 4) is true:
• 1) M is 1, ring A and ring B are meta to each other, and R1 to R9 comprise a total of at least 6 phenyl groups;
• 2) at least one of R1 to R4 is not hydrogen and at least one of R5 to R7 is not hydrogen;
• 3) R8 is phenyl and R9 is biphenyl;
• or
• 4) X is S.

A formulation comprising a compound of Formula I

• wherein:
• each of R1 to R7 is independently a hydrogen or a substituent selected from the group consisting of phenyl, and a system consisting of two to ten phenyl groups connected to each other;
• at least two of R1 to R7 are not hydrogen;
• if R1 and R3 are not hydrogen, then at least one of the following is true:
• 1) R1 and R3 are different from each other;
• or 2) at least one of R1 or R3 is an unsubstituted phenyl;
• if one of the at least two R1 to R7 that is not hydrogen is the system consisting of two to ten phenyl groups connected to each other, then the phenyl group directly bonded to the structure of Formula I having X bonds to exactly one phenyl group;
• R8 and R9 are each independently selected from the group consisting of phenyl, and a system consisting of two to ten phenyl groups connected to each other;
• X is selected from the group consisting of O, S, and Se;
• and
• L is selected from the group consisting of direct bond and
• wherein m is an integer from 1 to 5, and RA is a hydrogen or a substituent selected from the group consisting of aromatic and heteroaromatic rings;
• and
• subject to the following provisos i) to iv):
• i) if L is biphenyl, one phenyl of the biphenyl bonds to ring A and the other phenyl bonds to ring B;
• ii) if X is O, then least one of R1, R3, or R5 is H;
• iii) if X is S, then at least one of R1 or R6 is H but if R6 is H and R1 is not H, then at least one of R3 or R5 is H;
• and
• iv) the following structures are excluded
• and
• wherein at least one of the following conditions 1) to 4) is true:
• 1) m is 1, ring A and ring B are meta to each other, and R1 to R9 comprise a total of at least 6 phenyl groups;
• 2) at least one of R1 to R4 is not hydrogen and at least one of R5 to R7 is not hydrogen;
• 3) R8 is phenyl and R9 is biphenyl;
• or
• 4) X is S;
• and
• an h-host selected from the group consisting of:
• wherein:
• each of RA′, RB, RC, RD, RI, RJ, RK, RL, RM, RN, RO, RP, RQ, RR, RS, RT, RU, RV, and RW represent mono to the maximum allowable substitution, or no substitution;
• each of Ar2 and Ar4 is a linker independently selected from the group consisting of a direct bond, aryl, and heteroaryl;
• each of X1 and Y1 is independently selected from the group consisting of BRe′, NRe′, PRe′, O, S, Se, C═O, S═O, SO2, CRe′Rf′, SiRe′Rf′, and GeRe′Rf′;
• and
• each Ar3, R4′, R5′, R6′, R7′, R8′, Re′, Rf′, RA′, RB, RC, RD, RI, RJ, RK, RL, RM, RN, RO, RP, RQ, RR, RS, RT, RU, RV, and RW is independently a hydrogen or a substituent selected from the group consisting of deuterium, halogen, alkyl, cycloalkyl, heteroalkyl, heterocycloalkyl, boryl, arylalkyl, alkoxy, aryloxy, amino, silyl, alkenyl, cycloalkenyl, heteroalkenyl, alkynyl, aryl, heteroaryl, acyl, carboxylic acid, ether, ester, nitrile, isonitrile, sulfanyl, sulfinyl, sulfonyl, phosphino, and combinations thereof.