Plurality of host materials and organic electroluminescent device comprising the same

A plurality of host materials comprising at least one first host compound and at least second host compound, wherein the first host compound is represented by the following formula 1-1, and the second host compound is represented by the following formula 2:

• wherein
• Y1 and Y2, each independently, represents —N(L1-(Ar1)n)—, —O—, —S—, or —C(R1)(R2)—;
• with the proviso that Y1 and Y2 cannot simultaneously represent —O—;
• X1 to X12, each independently, represent —N═ or —C(Ra)═;
• and
• Ra, each independently, represents hydrogen, a halogen, a cyano, a substituted or unsubstituted (C1-C30)alkyl, or a substituted or unsubstituted (C3-C30)cycloalkyl;
• or adjacent Ra's may be linked to each other to form a ring(s), where if a plurality of Ra's are present, each of Ra may be the same or different;
• L1 represents a single bond, a substituted or unsubstituted (C1-C30)alkylene, a substituted or unsubstituted (C6-C30)arylene, a substituted or unsubstituted (3- to 30-membered)heteroarylene, or a substituted or unsubstituted (C3-C30)cycloalkylene;
• Ar1 represents a substituted or unsubstituted (C6-C30)aryl, a substituted or unsubstituted (3- to 30-membered)heteroaryl, or —N(R3)(R4);
• R1 to R4, each independently, represent hydrogen, deuterium, a halogen, a cyano, a substituted or unsubstituted (C1-C30)alkyl, a substituted or unsubstituted (C6-C30)aryl, a substituted or unsubstituted (3- to 30-membered)heteroaryl, or a substituted or unsubstituted (C3-C30)cycloalkyl;
• or may be linked to an adjacent substituent to form a ring(s);
• and
• n represents an integer of 1 or 2, where if n is 2, each of Ar1 may be the same or different;
• wherein
• X represents —N═, —NR35—, —O— or —S—;
• Z represents —N═, —NR36—, —O— or —S—, where if X represents —N═, Z represents —NR36—, —O— or —S—, and if X represents —NR35—, Z represents —N═, —O— or —S—;
• HAr represents a substituted or unsubstituted (3- to 30-membered)heteroaryl;
• R31 represents a substituted or unsubstituted (C6-C30)aryl, or a substituted or unsubstituted (3- to 30-membered)heteroaryl;
• R32 to R34, each independently, represent hydrogen, deuterium, a halogen, a cyano, a substituted or unsubstituted (C1-C30)alkyl, a substituted or unsubstituted (C6-C30)aryl, a substituted or unsubstituted (3- to 30-membered)heteroaryl, a substituted or unsubstituted (C3-C30)cycloalkyl, a substituted or unsubstituted (C1-C30)alkoxy, a substituted or unsubstituted tri(C1-C30)alkylsilyl, a substituted or unsubstituted di(C1-C30)alkyl(C6-C30)arylsilyl, a substituted or unsubstituted (C1-C30)alkyldi(C6-C30)arylsilyl, a substituted or unsubstituted tri(C6-C30)arylsilyl, or -L3-N(Ar2) (Ars);
• or may be linked to an adjacent substituent to form a ring(s);
• R35 and R36, each independently, represent hydrogen, deuterium, a halogen, a cyano, a substituted or unsubstituted (C1-C30)alkyl, a substituted or unsubstituted (C6-C30)aryl, a substituted or unsubstituted (3- to 30-membered)heteroaryl, a substituted or unsubstituted (C3-C30)cycloalkyl, a substituted or unsubstituted (C1-C30)alkoxy, a substituted or unsubstituted tri(C1-C30)alkylsilyl, a substituted or unsubstituted di(C1-C30)alkyl(C6-C30)arylsilyl, a substituted or unsubstituted (C1-C30)alkyldi(C6-C30)arylsilyl, a substituted or unsubstituted tri(C6-C30)arylsilyl, or -L3-N(Ar2) (Ar3);
• L2 and L3, each independently, represent a single bond, a substituted or unsubstituted (C6-C30)arylene, or a substituted or unsubstituted (3- to 30-membered)heteroarylene;
• Ar2 and Ar3, each independently, represent hydrogen, a substituted or unsubstituted (C1-C30)alkyl, a substituted or unsubstituted (C2-C30)alkenyl, a substituted or unsubstituted fused ring group of a (C3-C30) aliphatic ring(s) and a (C6-C30) aromatic ring(s), a substituted or unsubstituted (C6-C30)aryl, or a substituted or unsubstituted (3- to 30-membered)heteroaryl;
• and
• a′ represents 1, b′ and c′, each independently, represent an integer of 1 or 2, and d′ represents an integer of 1 to 4, where if each of b′, c′ and d′ is an integer of 2 or more, each of R32 to each of R34 may be the same or different.