Organic electroluminescence element and compound used therein
An organic electroluminescence element in which a compound represented by the general formula below is used in a light-emitting layer exhibits a high emission efficiency and is inexpensive to provide. At least one of R 1 to R 8 and R 17 represent an electron-donating group and the others represent a hydrogen atom; at least one of R 9 to R 16 represent an electron-withdrawing group that does not have an unshared electron pair at the α-position thereof and the others represent a hydrogen atom; Z represents a single bond or >C═Y; Y represents O, S, C(CN) 2 or C(COOH) 2 ; provided that when Z is a single bond, then at least one of R 9 to R 16 is an electron-withdrawing group that does not have an unshared electron pair at the α-position thereof.
1. An organic electroluminescence element having an anode, a cathode, and at least one organic layer containing a light-emitting layer between the anode and the cathode, wherein the light-emitting layer contains a compound represented by the following general formula (1):
wherein, in the general formula (1), R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 and R 17 each independently represent a hydrogen atom or an electron-donating group, and at least one of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 or R 17 is an electron-donating group; R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 and R 16 each independently represent a hydrogen atom, or an electron-withdrawing group that does not have an unshared electron pair at the α-position thereof; Z represents >C═Y, Y represents C(CN) 2 .
2. An organic electroluminescence element having an anode, a cathode, and at least one organic layer containing a light-emitting layer between the anode and the cathode, wherein the light-emitting layer contains a compound represented by the following general formula (1), which radiates delayed fluorescence:
wherein, in the general formula (1), R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 and R 17 each independently represent a hydrogen atom or an electron-donating group, and at least one of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 or R 17 is an electron-donating group; R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 and R 16 each independently represent a hydrogen atom, or an electron-withdrawing group that does not have an unshared electron pair at the α-position thereof; Z represents >C═Y, and Y represents O or C(CN) 2 .
3. The organic electroluminescence element according to claim 2 , wherein Z in the general formula (1) is a carbonyl group.
4. The organic electroluminescence element according to claim 1 , wherein R 17 in the general formula (1) is an aryl group.
5. The organic electroluminescence element according to claim 1 , wherein at least one of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 or R 8 in the general formula (1) is an aryl group substituted with an electron-donating group.
6. The organic electroluminescence element according to claim 1 , wherein at least one of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 or R 8 in the general formula (1) has a structure represented by the following general formula (2):
wherein, in the general formula (2), R 21 , R 22 , R 23 , R 24 and R 25 each independently represent a hydrogen atom or an electron-donating group, and at least one of R 21 , R 22 , R 23 , R 24 or R 25 is an electron-donating group.
7. The organic electroluminescence element according to claim 1 , wherein at least one of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 or R 8 in the general formula (1) has a structure represented by any of the following general formulae (3) to (5):
wherein, in the above formulae, R 31 and R 32 each independently represent a substituted or unsubstituted aryl group; and the aryl group represented by R 31 may bond to the aryl group represented by R 32 ; R 41 , R 42 and R 43 each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group; R 41 and R 42 may together form a cyclic structure, and R 42 and R 43 may together form a cyclic structure; R 51 , R 52 and R 53 each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group; R 51 and R 52 may together form a cyclic structure, and R 52 and R 53 may together form a cyclic structure.
8. The organic electroluminescence element according to claim 1 , wherein at least one of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 or R 8 in the general formula (1) has any of the following structures:
9. The organic electroluminescence element according to claim 1 , wherein at least one of R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 or R 16 is a cyano group or has a structure represented by any of the following general formulae (6) to (9):
wherein, in the above formulae, R 61 and R 62 each independently represent a substituted or unsubstituted aryl group; R 71 and R 72 each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group; and R 71 and R 72 may together form a cyclic structure; R 81 , R 82 and R 83 each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group; R 81 and R 82 may together form a cyclic structure, and R 82 and R 83 may together form a cyclic structure; R 91 represents a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group; and Z represents a linking group necessary for forming a heteroaromatic ring.
10. The organic electroluminescence element according to claim 1 , wherein at least one of R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 or R 16 in the general formula (1) has any of the following structures:
11. An organic electroluminescence element, wherein a compound represented by the following general formula (1) is used as a dopant in a light-emitting layer
wherein, in the general formula (1), R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 and R 17 each independently represent a hydrogen atom or an electron-donating group, and at least one of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 or R 17 is an electron-donating group; R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 and R 16 each independently represent a hydrogen atom, or an electron-withdrawing group that does not have an unshared electron pair at the α-position thereof; Z represents >C═Y, and Y represents O or C(CN) 2 .
12. A compound represented by the following general formula (1′):
wherein, in the general formula (1′), R 1′ , R 2′ , R 3′ , R 4′ , R 5′ , R 6′ , R 7′ , R 8′ , and R 17′ each independently represent a hydrogen atom or an electron-donating group, and at least one of R 1′ , R 2′ , R 3′ , R 4′ , R 5′ , R 6′ , R 7′ , R 8′ or R 17′ is an electron-donating group; R 9′ , R 10′ , R 11′ , R 12′ , R 13′ , R 14′ , R 15′ and R 16′ each independently represent a hydrogen atom or a cyano group; Z′ represents >C═Y, and Y represents O or C(CN) 2 .
13. The compound according to claim 12 , wherein Z′ in the general formula (1′) is a carbonyl group.
14. The compound according to claim 12 , wherein Z′ in the general formula (1′) is >C═C(CN) 2 .
15. The compound according to claim 12 , wherein R 17′ in the general formula (1′) is an aryl group.
16. The compound according to claim 12 , wherein at least one of R 1′ , R 2′ , R 3′ , R 4′ , R 5′ , R 6′ , R 7′ or R 8′ in the general formula (1′) is an aryl group substituted with an electron-donating group.
17. The compound according to claim 12 , wherein at least one of R 1′ , R 2′ , R 3′ , R 4′ , R 5′ , R 6′ , R 7′ or R 8′ in the general formula (1′) has a structure represented by the following general formula (2):
wherein, in the general formula (2), R 21 , R 22 , R 23 , R 24 and R 25 each independently represent a hydrogen atom or an electron-donating group, and at least one of R 21 , R 22 , R 23 , R 24 or R 25 is an electron-donating group.
18. The compound according to claim 12 , wherein at least one of R 1′ , R 2′ , R 3′ , R 4′ , R 5′ , R 6′ , R 7′ , or R 8′ in the general formula (1′) has a structure represented by any of the following general formulae (3) to (5):
wherein, in the above formulae, R 31 and R 32 each independently represent a substituted or unsubstituted aryl group; and the aryl group represented by R 31 may bond to the aryl group represented by R 32 ; R 41 , R 42 and R 43 each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group; R 41 and R 42 may together form a cyclic structure, and R 42 and R 43 may together form a cyclic structure; R 51 , R 52 and R 53 each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, or a substituted or unsubstituted aryl group; R 51 and R 52 may together form a cyclic structure, and R 52 and R 53 may together form a cyclic structure.
19. The compound according to claim 12 , wherein at least one of R 1′ , R 2′ , R 3′ , R 4′ , R 5′ , R 6′ , R 7′ or R 8′ in the general formula (1′) has any of the following structures:
20. A delayed fluorescence emitter having a structure represented by the following general formula (1):
wherein, in the general formula (1), R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 and R 17 each independently represent a hydrogen atom or an electron-donating group, and at least one of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 or R 17 is an electron-donating group; R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 and R 16 each independently represent a hydrogen atom, or an electron-withdrawing group that does not have an unshared electron pair at the α-position thereof; Z represents >C═Y, and Y represents O or C(CN) 2 .
21. A delayed fluorescence material comprising a compound represented by the following general formula (1′):
wherein, in the general formula (1′), R 1′ , R 2′ , R 3′ , R 4′ , R 5′ , R 6′ , R 7′ , R 8′ and R 17′ each independently represent a hydrogen atom or an electron-donating group, and at least one of tR 1′ , R 2′ , R 3′ , R 4′ , R 5′ , R 6′ , R 7′ , R 8′ or R 17′ is an electron donating group; R 9′ , R 10′ , R 11′ , R 12′ , R 13′ , R 14′ , R 15′ and R 16′ each independently represent a hydrogen atom or a cyano group; Z′ represents >C═Y, and Y represents O or C(CN) 2 .
22. In a method of providing delayed fluorescence or luminescence, comprising subjecting an electroluminescence element to a light inducing stimulus, the improvement wherein
the electroluminescence element comprises a delayed fluorescence emitter:
wherein, in the general formula (1), R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 and R 17 each independently represent a hydrogen atom or an electron-donating group, and at least one of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 or R 17 is an electron-donating group; R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 and R 16 each independently represent a hydrogen atom, or an electron-withdrawing group that does not have an unshared electron pair at the α-position thereof; Z represents >C═Y, and Y represents O or C(CN) 2 .
23. A light-emitting material comprising a compound represented by the following general formula (1):
wherein, in the general formula (1), R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 and R 17 each independently represent a hydrogen atom or an electron-donating group, and at least one of R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 or R 17 is an electron-donating group; R 9 , R 10 , R 11 , R 12 , R 13 , R 14 , R 15 and R 16 each independently represent a hydrogen atom, or an electron-withdrawing group that does not have an unshared electron pair at the α-position thereof; Z represents >C═Y, and Y represents O or C(CN) 2 .
24. In an organic electroluminescence display device comprising an organic electroluminescence element, wherein the improvement comprises that the organic electroluminescence element is in accordance with claim 11 .