PHOSPHOROUS HOST MATERIAL AND ORGANIC ELECTROLUMINESCENT DEVICE COMPRISING THE SAME

1 . A phosphorous host material comprising a compound represented by the following formula (4):

wherein

Z represents NR 4 ;

the structure of

in formula (4) is represented formula (7):

R 1 to R 4 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, a substituted or unsubstituted mono- or di-(C1-C30)alkylamino, a substituted or unsubstituted mono- or di-(C6-C30)arylamino, or a substituted or unsubstituted (C1-C30)alkyl(C6-C30)arylamino; or are linked to an adjacent substituent(s) to form a substituted or unsubstituted, mono- or polycyclic, (C3-C30) alicyclic or aromatic ring, whose carbon atom(s) may be replaced with at least one hetero atom selected from nitrogen, oxygen, and sulfur;

a and b each independently represent an integer of 1 to 4;

c represents 1 or 2;

where a, b, or c is an integer of 2 or more, each of R 1 , each of R 2 , or each of R 3 may be the same or different; and

the heteroaryl contains at least one hetero atom selected from B, N, O, S, Si, and P.

2 . The phosphorous host material according to claim 1 , wherein the substituents of the substituted (C1-C30)alkyl, the substituted (C6-C30)aryl, the substituted 3- to 30-membered heteroaryl, the substituted (C3-C30)cycloalkyl, the substituted (C1-C30)alkoxy, the substituted tri(C1-C30)alkylsilyl, the substituted di(C1-C30)alkyl(C6-C30)arylsilyl, the substituted (C1-C30)alkyldi(C6-C30)arylsilyl, the substituted tri(C6-C30)arylsilyl, the substituted mono- or di-(C1-C30)alkylamino, the substituted mono- or di-(C6-C30)arylamino, the substituted (C1-C30)alkyl(C6-C30)arylamino, and the substituted mono- or polycyclic, (C3-C30) alicyclic or aromatic ring in R 1 to R 8 each independently are at least one selected from the group consisting of deuterium, a halogen, a cyano, a carboxyl, a nitro, a hydroxyl, a (C1-C30)alkyl, a halo(C1-C30)alkyl, a (C2-C30) alkenyl, a (C2-C30) alkynyl, a (C1-C30)alkoxy, a (C1-C30)alkylthio, a (C3-C30)cycloalkyl, a (C3-C30)cycloalkenyl, a 3- to 7-membered heterocycloalkyl, a (C6-C30)aryloxy, a (C6-C30)arylthio, a 5- to 30-membered heteroaryl unsubstituted or substituted with a (C6-C30)aryl, a (C6-C30)aryl unsubstituted or substituted with a 5- to 30-membered heteroaryl, a tri(C1-C30)alkylsilyl, a tri(C6-C30)arylsilyl, a di(C1-C30)alkyl(C6-C30)arylsilyl, a (C1-C30)alkyldi(C6-C30)arylsilyl, an amino, a mono- or di-(C1-C30)alkylamino, a mono- or di-(C6-C30)arylamino, a (C1-C30)alkyl(C6-C30)arylamino, a (C1-C30)alkylcarbonyl, a (C1-C30)alkoxycarbonyl, a (C6-C30)arylcarbonyl, a di(C6-C30)arylboronyl, a di(C1-C30)alkylboronyl, a (C1-C30)alkyl(C6-C30)arylboronyl, a (C6-C30)aryl(C1-C30)alkyl, and a (C1-C30)alkyl(C6-C30)aryl.

3 . The phosphorous host material according to claim 1 , wherein R 1 to R 4 each independently represent hydrogen, a substituted or unsubstituted (C1-C6)alkyl, or a substituted or unsubstituted (C6-C15)aryl; or are linked to an adjacent substituent(s) to form a substituted or unsubstituted, mono- or polycyclic, (C3-C12) aromatic ring.

4 . The phosphorous host material according to claim 1 , wherein

R 1 and R 2 each independently represent hydrogen; or are linked to an adjacent substituent(s) to form a substituted or unsubstituted, monocyclic (C3-C12) aromatic ring; and

R 3 and R 4 each independently represents an unsubstituted (C1-C6)alkyl, or a (C6-C15)aryl unsubstituted or substituted with a (C1-C6)alkyl.

5 . The phosphorous host material according to claim 1 , wherein the compound represented by formula 4 is selected from the group consisting of:

6 . An organic electroluminescent device comprising the phosphorous host material according to claim 1 .