Organic electroluminescent element and electronic device
An organic EL device includes an emitting layer, a first layer adjacent to an anode-side of the emitting layer, and a second layer adjacent to a cathode-side thereof. The emitting layer contains first to third compounds. The first and second layers contain compounds of Formulae (1) and (2), respectively. The first and second compounds exhibits fluorescence and delayed fluorescence, respectively. Singlet energies S 1 of the first to third compounds satisfy S 1 (M3)>S 1 (M2)>S 1 (M1). In Formula (1), Ra 1 -Ra 5 , Rb 1 -Rb 5 and Rc 1 -Rc 5 are each a substituent, etc. In Formula (2), X 1 -X 3 are each nitrogen atom, etc, Ar 1 -Ar 2 are each a group of Formula (2A) or aryl group, etc, A is a group of Formula (2A) in which HAr is of Formula (2B), a is 1 to 5, L 1 is a linking group, etc. In Formula (2B), X 11 -X 18 are each nitrogen atom, etc, and Y 1 is oxygen, sulfur or nitrogen atom, etc,
1 . An organic electroluminescence device comprising:
an anode;
a cathode;
an emitting layer provided between the anode and the cathode;
a first layer provided between the anode and the emitting layer and adjacent to the emitting layer; and
a second layer provided between the cathode and the emitting layer and adjacent to the emitting layer, wherein
the emitting layer comprises a first compound, a second compound, and a third compound,
the first layer comprises a compound represented by formula (1),
the second layer comprises a compound represented by formula (2),
the first compound is a fluorescent compound,
the second compound is a delayed fluorescent compound, and
a singlet energy S 1 (M1) of the first compound, a singlet energy S 1 (M2) of the second compound, and a singlet energy S 1 (M3) of the third compound satisfy a relationship of Numerical Formula 1,
S
1
(
M
3
)
>
S
1
(
M
2
)
>
S
1
(
M
1
)
(
Numerical
Formula
1
)
wherein
Ra 1 to Ra 5 , Rb 1 to Rb 5 , and Rc 3 to Rc 5 are each independently a hydrogen atom or a substituent;
with the proviso that one of Ra 1 to Ra 5 is a substituent and the Ra 1 to Ra 5 not being a substituent are each hydrogen atoms and one of Rb 1 to Rb 5 is a substituent and the Rb 1 to Rb 5 not being a substituent are each hydrogen atoms,
Ra 1 to Ra 5 , Rb 1 to Rb 5 , and Rc 3 to Rc 5 serving as the substituent are each independently a halogen atom, a cyano group, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms;
Rc 1 is a hydrogen atom or a substituent, or is bonded to Rc 2 to form a ring, and Rc 1 serving as the substituent is a substituted or unsubstituted aryl group having 6 to 12 ring carbon atoms;
Rc 2 is a hydrogen atom or a substituent, or a pair of Rc 1 and Rc 2 are mutually bonded to form a ring;
when a pair of Rc 1 and Rc 2 are mutually bonded to form a ring, the ring at least comprises a five-membered ring, the five-membered ring comprising at least one of a carbon atom, an oxygen atom, a sulfur atom, or a nitrogen atom;
Rc 1 and Rc 2 are not hydrogen atoms at the same time; and
Rc 2 serving as the substituent is a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms, a substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms, a substituted or unsubstituted arylthio group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted amino group,
wherein
a partial structure represented by formula (1A) in formula (1) is a group represented by one of formulae (1A-1) and (1A-3) to (1A-10),
wherein
Rc 1 represents the same as Rc 1 in the formula (1), Rc 2 represents the same as Rc 2 in the formula (1), Rc 3 to Rc 5 each independently represent the same as Rc 3 to Rc 5 in the formula (1), and * represents a bonding position to a nitrogen atom in the compound represented by the formula (1),
where in the formulae (1A-1) and (1A-3) to (1A-10);
R A is a hydrogen atom or a substituent;
R A serving as the substituent is each independently a halogen atom, a cyano group, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 30 carbon atoms, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, or a substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms;
when a plurality of R A are present, the plurality of R A are mutually the same or different; and * represents a bonding position to a nitrogen atom in the compound represented by the formula (1),
wherein
X 1 to X 3 are each independently a nitrogen atom or CR 1 , at least one of X 1 to X 3 is a nitrogen atom;
R 1 is a hydrogen atom or a substituent;
R 1 serving as the substituent is each independently a halogen atom, a cyano group, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 30 carbon atoms, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, or a substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms;
Ar 1 and Ar 2 are each independently represented by formula (2A), or a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms; and
A is represented by formula (2A) below,
wherein
HAr is represented by formula (2B);
a is 1, 2, 3, 4 or 5;
when a is 1, L 1 is a single bond or a divalent linking group;
when a is 2, 3, 4 or 5, L 1 is a trivalent to hexavalent linking group;
a plurality of HAr are mutually the same or different;
the linking group is a group derived from a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a group derived from a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms, a group derived from a group formed by mutually bonding two groups selected from the group consisting of a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms and a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms, or a group derived from a group formed by mutually bonding three groups selected from the group consisting of a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms and a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms; and
the mutually bonded groups are mutually the same or different,
wherein
X 11 to X 18 are each independently a nitrogen atom, CR 13 , or a carbon atom bonded to L 1 ;
a plurality of R 13 are mutually the same or different;
Y 1 is an oxygen atom, a sulfur atom, NR 18 , SiR 11 R 12 , CR 14 R 15 , a nitrogen atom bonded to L 1 , a silicon atom bonded to each of R 16 and L 1 , or a carbon atom bonded to each of R 17 and L 1 ;
among carbon atoms in X 11 to X 18 , R 11 to R 12 , and R 14 to R 15 as well as a nitrogen atom, a silicon atom, and carbon atoms in Y 1 , one atom is bonded to L 1 ;
R 11 and R 12 are the same or different; R 14 and R 15 are the same or different;
R 18 and R 11 to R 17 are each independently a hydrogen atom or a substituent, or at least one pair of a pair of adjacent ones of R 13 , a pair of R 11 and R 12 , or a pair of R 14 and R 15 are bonded to each other to form a ring; and
R 18 and R 11 to R 17 serving as the substituent are each independently a halogen atom, a cyano group, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 30 carbon atoms, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, or a substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms.
2 . The organic electroluminescence device according to claim 1 , wherein
the group represented by formula (1A) is one of formulae (1A-1), (1A-3) to (1A-5) and (1A-10).
3 . The organic electroluminescence device according to claim 1 , wherein
the group represented by formula (1A) is formula (1A-1) or formula (1A-4).
4 . The organic electroluminescence device according to claim 1 , wherein
the group represented by formula (1A) is one of formulae (1A-6) to (1A-9).
5 . The organic electroluminescence device according to claim 4 , wherein
the group represented by formula (1A) is formula (1A-9).
6 . The organic electroluminescence device according to claim 1 , wherein
the group represented by formula (1A) is formula (1A-1), (1A-4) or (1A-9).
7 . The organic electroluminescence device according to claim 1 , wherein
the one of Ra 1 to Ra 5 and the one of Rb 1 to Rb 5 serving as the substituent is a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms.
8 . The organic electroluminescence device according to claim 1 , wherein
the one of Ra 1 to Ra 5 serving as the substituent is a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, and
the one of Rb 1 to Rb 5 serving as the substituent is a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms.
9 . The organic electroluminescence device according to claim 1 , wherein
the one of Ra 1 to Ra 5 serving as the substituent is an aryl group having 6 to 30 ring carbon atoms and substituted by a heteroaryl group having 5 to 30 ring atom, and
the one of Rb 1 to Rb 5 serving as the substituent is a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms.
10 . The organic electroluminescence device according to claim 1 , wherein
the one of Ra 1 to Ra 5 serving as the substituent and the one of Rb 1 to Rb 5 serving as the substituent are each independently selected from the group consisting of a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms.
11 . The organic electroluminescence device according to claim 1 , wherein
the one of Ra 1 to Ra 5 serving as the substituent, and the one of Rb 1 to Rb 5 serving as the substituent, are each independently selected from the group consisting of a halogen atom, a cyano group, an unsubstituted aryl group having 6 to 30 ring carbon atoms, and an unsubstituted heteroaryl group having 5 to 30 ring atoms.
12 . The organic electroluminescence device according to claim 1 , wherein
the one of Ra 1 to Ra 5 serving as the substituent is a group of formulae (1B-1) to (1B-10) and the one of Rb 1 to Rb 5 serving as the substituent is of formulae (1B-1) to (1B-10),
wherein
R B is a hydrogen atom or a substituent;
R B serving as the substituent is each independently a halogen atom, a cyano group, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 30 carbon atoms, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, or a substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms;
when a plurality of R B are present, the plurality of R B are mutually the same or different; and * each represents a bonding position to a benzene ring bonded to Ra 1 to Ra 5 or a bonding position to a benzene ring bonded to Rb 1 to Rb 5 in the compound represented by the formula (1).
13 . The organic electroluminescence device according to claim 1 , wherein
the compound represented by formula (1) is a compound represented by formula (1X), formula (1Y) or formula (1Z),
wherein
one of Ra 1 to Ra 5 is a group represented by one of formulae (1B-1) to (1B-10);
one of Rb 1 to Rb 5 is a group represented by one of formulae (1B-1) to (1B-10);
R A is a hydrogen atom or a substituent, and R A serving as the substituent is each independently a halogen atom, a cyano group, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 30 carbon atoms, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, or a substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms; and
when a plurality of R A are present, the plurality of R A are the same or different,
wherein
R B is a hydrogen atom or a substituent, and R B as the substituent is each independently a halogen atom, a cyano group, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 30 carbon atoms, a substituted or unsubstituted silyl group, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, or a substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms;
when a plurality of R are present, the plurality of R B are mutually the same or different; and * each represents a bonding position to a benzene ring bonded to Ra 1 to Ra 5 or a bonding position to a benzene ring bonded to Rb 1 to Rb 5 in the compound represented by the formula (1).
14 . The organic electroluminescence device according to claim 13 , wherein
R A is a hydrogen atom.
15 . The organic electroluminescence device according to claim 1 , wherein
an ionization potential Ip of the compound represented by formula (1) is 5.78 eV or more.
16 . The organic electroluminescence device according to claim 1 , wherein
two or three of X 1 to X 3 are nitrogen atoms.
17 . The organic electroluminescence device according to claim 1 , wherein
L 1 is a trivalent to hexavalent residue derived from a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms.
18 . The organic electroluminescence device according to claim 1 , wherein
a is 1 or 2, and
L 1 is a divalent or trivalent linking group.
19 . The organic electroluminescence device according to claim 18 , wherein
L 1 is a divalent or trivalent linking group derived from benzene, biphenyl, terphenyl, naphthalene, and phenanthrene.
20 . The organic electroluminescence device according to claim 1 , wherein
a is 2 and
L 1 is a trivalent residue derived from a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or a trivalent residue derived from a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms.
21 . The organic electroluminescence device according to claim 1 , wherein
L 1 is a single bond.
22 . The organic electroluminescence device according to claim 1 , wherein
Y 1 is NR 18 , or a nitrogen atom bonded to L 1 .
23 . The organic electroluminescence device according to claim 1 , wherein
Y 1 is CR 14 R 15 .
24 . The organic electroluminescence device according to claim 1 , wherein
Y 1 is an oxygen atom or a sulfur atom.
25 . The organic electroluminescence device according to claim 1 , wherein
Y 1 is an oxygen atom or a sulfur atom, and
one of X 11 to X 18 is a carbon atom bonded to L 1 and the rest of X 11 to X 18 are each CR 13 .
26 . The organic electroluminescence device according to claim 1 , wherein
X 13 or X 16 is a carbon atom bonded to L 1 .
27 . The organic electroluminescence device according to claim 1 , wherein
a substituent for a substituted or unsubstituted group is a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkyl halide group having 1 to 30 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 30 ring carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted alkoxy halide group having 1 to 30 carbon atoms, a substituted or unsubstituted alkylthio group having 1 to 30 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 ring carbon atoms, a substituted or unsubstituted arylthio group having 6 to 30 ring carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted alkynyl group having 2 to 30 carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, a substituted or unsubstituted alkylsulfonyl group having 1 to 30 carbon atoms, a substituted or unsubstituted arylcarbonyl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted acyl group having 1 to 30 carbon atoms, a halogen atom, a carboxy group, a substituted or unsubstituted amino group, a nitro group, a cyano group, a substituted or unsubstituted silyl group, a substituted phosphoryl group, a hydroxy group, a substituted phosphino group, an ester group, a siloxanyl group, or a carbamoyl group.
28 . The organic electroluminescence device according to claim 1 , wherein
a substituent for a substituted or unsubstituted group is selected from the group consisting of a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkyl halide group having 1 to 30 carbon atoms, and a substituted or unsubstituted cycloalkyl group having 3 to 30 ring carbon atoms.
29 . The organic electroluminescence device according to claim 1 , wherein
a substituent for a substituted or unsubstituted group is selected from the group consisting of a substituted or unsubstituted aryl group having 6 to 12 ring carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 12 ring atoms, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted alkyl halide group having 1 to 6 carbon atoms, and a substituted or unsubstituted cycloalkyl group having 3 to 12 ring carbon atoms.
30 . The organic electroluminescence device according to claim 1 , wherein
the emitting layer does not comprise a metal complex.
31 . An electronic device comprising the organic electroluminescence device according to claim 1 .