# US 12,004,422 B2 · Heterocyclic compound and organic light-emitting device including the same

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- Number: US 12,004,422 B2
- Document ID: US12004422B2
- Status: Granted
- Kind: B2
- Application number: 16/672,159
- Filed: 2019-11-01
- Published: 2020-09-17
- Granted: 2024-06-04
- Earliest claimed: 2019-03-11
- Assignees: Samsung Display Co., Ltd.
- Applicants: Samsung Display Co., Ltd.
- Inventors: Yeseul Lee; Hyeongmin Kim; Heechoon Ahn; Hyunah Um; Yirang Im; Soobyung Ko; Jongwoo Kim
- Web page: https://patentgrep.com/patent/US12004422B2

## CPC

- C07D 409/14: containing three or more hetero rings
- C07D 209/86: with only hydrogen atoms, hydrocarbon or substituted hydrocarbon radicals, directly attached to carbon atoms of the ring system
- C07D 405/14: containing three or more hetero rings
- C07D 413/14: containing three or more hetero rings
- C07D 417/14: containing three or more hetero rings
- C07D 471/14: Ortho-condensed systems
- C07F 7/0812: {comprising a heterocyclic ring}
- C07F 7/0814: {said ring is substituted at a C ring atom by Si}
- C09K 11/06: containing organic luminescent materials
- H10K 85/40: Organosilicon compounds, e.g. TIPS pentacene
- H10K 85/615: {Polycyclic condensed aromatic hydrocarbons, e.g. anthracene}
- H10K 85/657: {Polycyclic condensed heteroaromatic hydrocarbons}
- H10K 85/6572: {comprising only nitrogen in the heteroaromatic polycondensed ring system, e.g. phenanthroline or carbazole}
- H10K 85/6574: {comprising only oxygen in the heteroaromatic polycondensed ring system, e.g. cumarine dyes}
- H10K 85/6576: {comprising only sulfur in the heteroaromatic polycondensed ring system, e.g. benzothiophene}
- H10K 50/11: characterised by the electroluminescent [EL] layers
- H10K 50/12: comprising dopants
- H10K 50/15: Hole transporting layers
- H10K 50/16: Electron transporting layers
- H10K 2101/10: Triplet emission
- C07D: HETEROCYCLIC COMPOUNDS (macromolecular compounds C08)
- C07F: ACYCLIC, CARBOCYCLIC OR HETEROCYCLIC COMPOUNDS CONTAINING ELEMENTS OTHER THAN CARBON, HYDROGEN, HALOGEN, OXYGEN, NITROGEN, SULFUR, SELENIUM OR TELLURIUM (metal-containing porphyrins C07D487/22)
- C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
- H10K: ORGANIC ELECTRIC SOLID-STATE DEVICES

## Abstract

Provided are a heterocyclic compound represented by a certain formula and an organic light-emitting device including the same.

## Claims

### Claim 1

An organic light-emitting device comprising:
a first electrode;
a second electrode facing the first electrode;
an organic layer between the first electrode and the second electrode and comprising an emission layer; and
at least one heterocyclic compound represented by one of Formulae 1-1A, 1-1B, 1-2A, 1-3A, 1-3B, 1-4A, and 1-4B:
wherein, in Formulae 1-1A, 1-1B, 1-2A, 1-3A, 1-3B, 1-4A, and 1-4B,
in Formula 1-1A, 1-1B, 1-3A, 1-3B, 1-4A, and 1-4B, Ar1 is selected from groups represented by Formulae 6-1 to 6-35, and
in Formula 1-2A, Ar1 is selected from groups represented by Formulae 6-1 to 6-33 and 6-35:
wherein, in Formulae 6-1 to 6-35,
Ph indicates a phenyl group, t-Bu indicates a tert-butyl group, and Cz indicates a carbazolyl group, and
* indicates a binding site to a neighboring atom,
D1a and D1b are each independently a group represented by Formula 2, and
D1a and D1b are identical to or different from each other:
wherein, in Formula 2,
X1 is selected from a single bond, C(R5)(R6), Si(R5)(R6), N(R5), O, and S,
A1 and A2 are each independently a C5-C60 carbocyclic group or a C1-C60 heterocyclic group,
a1 is 0,
* indicates a binding site to a neighboring atom,
in Formulae 1-1A, 1-1B, 1-2A, 1-3A, 1-3B, 1-4A, 1-4B, and 2,
R1 to R6 are each independently selected from hydrogen, deuterium, —F —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a substituted or unsubstituted C1-C60 alkyl group, a substituted or unsubstituted C2-C60 alkenyl group, a substituted or unsubstituted C2-C60 alkynyl group, a substituted or unsubstituted C1-C60 alkoxy group, a substituted or unsubstituted C3-C10 cycloalkyl group, a substituted or unsubstituted C1-C10 heterocycloalkyl group, a substituted or unsubstituted C3-C10 cycloalkenyl group, a substituted or unsubstituted C1-C10 heterocycloalkenyl group, a substituted or unsubstituted C6-C60 aryl group, a substituted or unsubstituted C6-C60 aryloxy group, a substituted or unsubstituted C6-C60 arylthio group, a substituted or unsubstituted C1-C60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —Si(Q1)(Q2)(Q3), —N(Q1)(Q2), —B(Q1)(Q2), —S(═O)2(Q1), and —P(═O)(Q1)(Q2),
except that
in Formulae 1-1A, 1-1B, 1-2A, 1-3A, 1-3B, 1-4A, and 1-4B, R1 is not a C1-C60 alkyl group substituted with three —F, and R2 is not a C1-C60 alkyl group substituted with three —F, and
in Formulae 1-3A, 1-3B, 1-4A, and 1-4B, R1 and
R2 are each hydrogen,
c1 is an integer from 1 to 3,
c2 is an integer from 1 to 4,
c3 and c4 are each independently an integer from 1 to 5,
at least one substituent of the substituted C3-C10 cycloalkylene group, the substituted C1-C10 heterocycloalkylene group, the substituted C3-C10 cycloalkenylene group, the substituted C1-C10 heterocycloalkenylene group, the substituted C6-C60 arylene group, the substituted C1-C60 heteroarylene group, the substituted divalent non-aromatic condensed polycyclic group, the substituted divalent non-aromatic condensed heteropolycyclic group, the substituted C1-C60 alkyl group, the substituted C2-C60 alkenyl group, the substituted C2-C60 alkynyl group, the substituted C1-C60 alkoxy group, the substituted C3-C10 cycloalkyl group, the substituted C1-C10 heterocycloalkyl group, the substituted C3-C10 cycloalkenyl group, the substituted C1-C10 heterocycloalkenyl group, the substituted C6-C60 aryl group, the substituted C6-C60 aryloxy group, the substituted C6-C60 arylthio group, the substituted C1-C60 heteroaryl group, the substituted monovalent non-aromatic condensed polycyclic group, and the substituted monovalent non-aromatic condensed heteropolycyclic group is selected from:
deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C1-C60 alkyl group, a C2-C60 alkenyl group, a C2-C60 alkynyl group, and a C1-C60 alkoxy group;
a C1-C60 alkyl group, a C2-C60 alkenyl group, a C2-C60 alkynyl group, and a C1-C60 alkoxy group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C3-C10 cycloalkyl group, a C1-C10 heterocycloalkyl group, a C3-C10 cycloalkenyl group, a C1-C10 heterocycloalkenyl group, a C6-C60 aryl group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C1-C60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —Si(Q11)(Q12)(Q13), —N(Q11)(Q12), —B(Q11)(Q12), —C(═O)(Q11), —S(═O)2(Q11), and —P(═O)(Q11)(Q12);
a C3-C10 cycloalkyl group, a C1-C10 heterocycloalkyl group, a C3-C10 cycloalkenyl group, a C1-C10 heterocycloalkenyl group, a C6-C60 aryl group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C1-C60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group;
a C3-C10 cycloalkyl group, a C1-C10 heterocycloalkyl group, a C3-C10 cycloalkenyl group, a C1-C10 heterocycloalkenyl group, a C6-C60 aryl group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C1-C60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C1-C60 alkyl group, a C2-C60 alkenyl group, a C2-C60 alkynyl group, a C1-C60 alkoxy group, a C3-C10 cycloalkyl group, a C1-C10 heterocycloalkyl group, a C3-C10 cycloalkenyl group, a C1-C10 heterocycloalkenyl group, a C6-C60 aryl group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C1-C60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —Si(Q21)(Q22)(Q23), —N(Q21)(Q22), —B(Q21)(Q22), —C(═O)(Q21), —S(═O)2(Q21), and —P(═O)(Q21)(Q22), and
—Si(Q31)(Q32)(Q33), —N(Q31)(Q32), —B(Q31)(Q32), —C(═O)(Q31), —S(═O)2(Q31), and —P(═O)(Q31)(Q32), and
Q1 to Q3, Q11 to Q13, Q21 to Q23, and Q31 to Q33 are each independently selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C1-C60 alkyl group, a C2-C60 alkenyl group, a C2-C60 alkynyl group, a C1-C60 alkoxy group, a C3-C10 cycloalkyl group, a C1-C10 heterocycloalkyl group, a C3-C10 cycloalkenyl group, a C1-C10 heterocycloalkenyl group, a C6-C60 aryl group, a C1-C60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, a biphenyl group, and a terphenyl group.

### Claim 2 (depends on 1)

The organic light-emitting device of claim 1, wherein
the first electrode is an anode,
the second electrode is a cathode,
the organic layer comprises the at least one heterocyclic compound,
the organic layer further comprises a hole transport region between the first electrode and the emission layer and an electron transport region between the emission layer and the second electrode,
the hole transport region comprises a hole injection layer, a hole transport layer, an emission auxiliary layer, an electron blocking layer, or any combination thereof, and
the electron transport region comprises a hole blocking layer, an electron transport layer, an electron injection layer, or any combination thereof.

### Claim 3 (depends on 2)

The organic light-emitting device of claim 2, wherein
the hole transport region comprises a hole transport layer, and
the hole transport layer comprises a first hole transport layer and a second hole transport layer.

### Claim 4 (depends on 2)

The organic light-emitting device of claim 2, wherein
the electron transport region comprises at least one selected from a phosphine oxide-containing compound, a silyl-containing compound, and a silyl-substituted phosphine oxide-containing compound.

### Claim 5 (depends on 1)

The organic light-emitting device of claim 1, wherein
the emission layer comprises the at least one heterocyclic compound.

### Claim 6 (depends on 5)

The organic light-emitting device of claim 5, wherein
the emission layer emits blue light having a wavelength of maximum emission in a range of about 390 nm to about 440 nm.

### Claim 7 (depends on 5)

The organic light-emitting device of claim 5, wherein
the emission layer further comprises a phosphorescent dopant or a fluorescent dopant.

### Claim 8 (depends on 7)

The organic light-emitting device of claim 7, wherein
the phosphorescent dopant comprises an organometallic complex represented by Formula 401:
wherein, in Formulae 401 and 402,
M is selected from iridium (Ir), platinum (Pt), palladium (Pd), osmium (Os), titanium (Ti), zirconium (Zr), hafnium (Hf), europium (Eu), terbium (Tb), rhodium (Rh), and thulium (Tm),
L401 is selected from ligands represented by Formula 402, and xc1 is 1, 2, or 3, wherein, when xc1 is 2 or more, two or more L401(s) are identical to or different from each other,
L402 is an organic ligand, and xc2 is an integer from 0 to 4, wherein, when xc2 is 2 or more, two or more L402(s) are identical to or different from each other,
X401 to X404 are each independently nitrogen or carbon,
X401 and X403 are linked via a single bond or a double bond, and X402 and X404 are linked via a single bond or a double bond,
A401 and A402 are each independently a C5-C60 carbocyclic group or a C1-C60 heterocyclic group,
X405 is a single bond, *—O—*′, *—S—*′, *—C(═O)—*′, *—N(Q411)-*′, *—C(Q411)(Q412)-*′, *—C(Q411)═C(Q412)-*′, *—C(Q411)=*′, or *═C(Q411)=*′, wherein Q411 and Q412 are each independently hydrogen, deuterium, a C1-C20 alkyl group, a C1-C20 alkoxy group, a phenyl group, a biphenyl group, a terphenyl group, or a naphthyl group,
X406 is a single bond, O, or S,
R401 and R402 are each independently selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a substituted or unsubstituted C1-C20 alkyl group, a substituted or unsubstituted C1-C20 alkoxy group, a substituted or unsubstituted C3-C10 cycloalkyl group, a substituted or unsubstituted C1-C10 heterocycloalkyl group, a substituted or unsubstituted C3-C10 cycloalkenyl group, a substituted or unsubstituted C1-C10 heterocycloalkenyl group, a substituted or unsubstituted C6-C60 aryl group, a substituted or unsubstituted C6-C60 aryloxy group, a substituted or unsubstituted C6-C60 arylthio group, a substituted or unsubstituted C1-C60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —Si(Q401)(Q402)(Q403), —N(Q401)(Q402), —B(Q401)(Q402), —C(═O)(Q401), —S(═O)2(Q401), and —P(═O)(Q401)(Q402), wherein Q401 to Q403 are each independently selected from a C1-C10 alkyl group, a C1-C10 alkoxy group, a C6-C20 aryl group, and a C1-C20 heteroaryl group,
xc11 and xc12 are each independently an integer from 0 to 10, and
* and *′ in Formula 402 each indicate a binding site to M in Formula 401.

### Claim 9

A heterocyclic compound represented by one of Formulae 1-1A, 1-1B, 1-2A, 1-3A, 1-3B, 1-4A, and 1-4B:
wherein, in Formulae 1-1A, 1-1B, 1-2A, 1-3A, 1-3B, 1-4A, and 1-4B,
in Formulae 1-1A, 1-1B, 1-3A, 1-3B, 1-4A, and 1-4B, Ar1 is selectee from groups represented by Formulae 6-1 to 6-35, and
in Formula 1-2A, Ar1 is selected from groups represented by Formulae 6-1 to 6-33 and 6-35:
wherein, in Formulae 6-1 to 6-35,
Ph indicates a phenyl group, t-Bu indicates a tert-butyl group, and Cz indicates a carbazolyl group, and
* indicates a binding site to a neighboring atom,
D1a and D1b are each independently a group represented by Formula 2, and
D1a and D1b are identical to or different from each other:
wherein, in Formula 2,
X1 is selected from a single bond, C(R5)(R6), Si(R5)(R6), N(R5), O, and S,
A1 and A2 are each independently a C5-C60 carbocyclic group or a C1-C60 heterocyclic group,
a1 is 0,
* indicates a binding site to a neighboring atom,
in Formulae 1-1A, 1-1B, 1-2A, 1-3A, 1-3B, 1-4A, 1-4B, and 2,
R1 to R6 are each independently selected from hydrogen, deuterium, —F —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a carboxylic acid group or a salt thereof, a sulfonic acid group or a salt thereof, a phosphoric acid group or a salt thereof, a substituted or unsubstituted C1-C60 alkyl group, a substituted or unsubstituted C2-C60 alkenyl group, a substituted or unsubstituted C2-C60 alkynyl group, a substituted or unsubstituted C1-C60 alkoxy group, a substituted or unsubstituted C3-C10 cycloalkyl group, a substituted or unsubstituted C1-C10 heterocycloalkyl group, a substituted or unsubstituted C3-C10 cycloalkenyl group, a substituted or unsubstituted heterocycloalkenyl group, a substituted or unsubstituted C6-C60 aryl group, a substituted or unsubstituted C6-C60 aryloxy group, a substituted or unsubstituted C6-C60 arylthio group, a substituted or unsubstituted C1-C60 heteroaryl group, a substituted or unsubstituted monovalent non-aromatic condensed polycyclic group, a substituted or unsubstituted monovalent non-aromatic condensed heteropolycyclic group, —Si(Q1)(Q2)(Q3), —N(Q1)(Q2), —B(Q1)(Q2), —S(═O)2(Q1), and —P(═O)(Q1)(Q2),
except that
in Formulae 1-1A, 1-1B, 1-2A, 1-3A, 1-3B, 1-4A, and 1-4B, R1 is not a C1-C60 alkyl group substituted with three —F, and R2 is not a C1-C60 alkyl group substituted with three —F, and
in Formulae 1-3A, 1-3B, 1-4A, and 1-4B, R1 and
R2 are each hydrogen,
c1 is an integer from 1 to 3,
c2 is an integer from 1 to 4,
c3 and c4 are each independently an integer from 1 to 5,
at least one substituent of the substituted C3-C10 cycloalkylene group, the substituted C1-C10 heterocycloalkylene group, the substituted C3-C10 cycloalkenylene group, the substituted C1-C10 heterocycloalkenylene group, the substituted C6-C60 arylene group, the substituted C1-C60 heteroarylene group, the substituted divalent non-aromatic condensed polycyclic group, the substituted divalent non-aromatic condensed heteropolycyclic group, the substituted C1-C60 alkyl group, the substituted C2-C60 alkenyl group, the substituted C2-C60 alkynyl group, the substituted C1-C60 alkoxy group, the substituted C3-C10 cycloalkyl group, the substituted C1-C10 heterocycloalkyl group, the substituted C3-C10 cycloalkenyl group, the substituted C1-C10 heterocycloalkenyl group, the substituted C6-C60 aryl group, the substituted C6-C60 aryloxy group, the substituted C6-C60 arylthio group, the substituted C1-C60 heteroaryl group, the substituted monovalent non-aromatic condensed polycyclic group, and the substituted monovalent non-aromatic condensed heteropolycyclic group is selected from:
deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C1-C60 alkyl group, a C2-C60 alkenyl group, a C2-C60 alkynyl group, and a C1-C60 alkoxy group;
a C1-C60 alkyl group, a C2-C60 alkenyl group, a C2-C60 alkynyl group, and a C1-C60 alkoxy group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C3-C10 cycloalkyl group, a C1-C10 heterocycloalkyl group, a C3-C10 cycloalkenyl group, a C1-C10 heterocycloalkenyl group, a C6-C60 aryl group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C1-C60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —Si(Q11)(Q12)(Q13), —N(Q11)(Q12), —B(Q11)(Q12), —C(═O)(Q11), —S(═O)2(Q11), and —P(═O)(Q11)(Q12);
a C3-C10 cycloalkyl group, a C1-C10 heterocycloalkyl group, a C3-C10 cycloalkenyl group, a C1-C10 heterocycloalkenyl group, a C6-C60 aryl group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C1-C60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group;
a C3-C10 cycloalkyl group, a C1-C10 heterocycloalkyl group, a C3-C10 cycloalkenyl group, a C1-C10 heterocycloalkenyl group, a C6-C60 aryl group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C1-C60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, and a monovalent non-aromatic condensed heteropolycyclic group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C1-C60 alkyl group, a C2-C60 alkenyl group, a C2-C60 alkynyl group, a C1-C60 alkoxy group, a C3-C10 cycloalkyl group, a C1-C10 heterocycloalkyl group, a C3-C10 cycloalkenyl group, a C1-C10 heterocycloalkenyl group, a C6-C60 aryl group, a C6-C60 aryloxy group, a C6-C60 arylthio group, a C1-C60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, —Si(Q21)(Q22)(Q23), —N(Q21)(Q22), —B(Q21)(Q22), —C(═O)(Q21), —S(═O)2(Q21), and —P(═O)(Q21)(Q22); and
—Si(Q31)(Q32)(Q33), —N(Q31)(Q32), —B(Q31)(Q32), —C(═O)(Q31), —S(═O)2(Q31), and —P(═O)(Q31)(Q32), and
Q1 to Q3, Q11 to Q13, Q21 to Q23, and Q31 to Q33 are each independently selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C1-C60 alkyl group, a C2-C60 alkenyl group, a C2-C60 alkynyl group, a C1-C60 alkoxy group, a C3-C10 cycloalkyl group, a C1-C10 heterocycloalkyl group, a C3-C10 cycloalkenyl group, a C1-C10 heterocycloalkenyl group, a C6-C60 aryl group, a C1-C60 heteroaryl group, a monovalent non-aromatic condensed polycyclic group, a monovalent non-aromatic condensed heteropolycyclic group, a biphenyl group, and a terphenyl group.

### Claim 10 (depends on 9)

The heterocyclic compound of claim 9, wherein
D1a and D1b are each independently selected from:
a carbazolyl group, a 9,10-dihydroacridinyl group, a phenoxazinyl group, a phenothiazinyl group, a benzocarbazolyl group, and a dibenzocarbazolyl group; and
a carbazolyl group, a 9,10-dihydroacridinyl group, a phenoxazinyl group, a phenothiazinyl group, a benzocarbazolyl group, and a dibenzocarbazolyl group, each substituted with at least one selected from deuterium, —F, —Cl, —Br, —I, a hydroxyl group, a cyano group, a nitro group, an amidino group, a hydrazino group, a hydrazono group, a C1-C20 alkyl group, a C1-C20 alkoxy group, a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, a cyclopentenyl group, a cyclohexenyl group, a phenyl group, a naphthyl group, a fluorenyl group, a spiro-bifluorenyl group, a spiro-fluorene-benzofluorenyl group, a benzofluorenyl group, a dibenzofluorenyl group, a phenalenyl group, a phenanthrenyl group, an anthracenyl group, a fluoranthenyl group, a triphenylenyl group, a pyridinyl group, a pyrazinyl group, a pyrimidinyl group, a quinolinyl group, an isoquinolinyl group, a benzoquinolinyl group, a naphthyridinyl group, a quinoxalinyl group, a quinazolinyl group, a carbazolyl group, a phenanthridinyl group, an acridinyl group, a phenanthrolinyl group, a phenazinyl group, a triazinyl group, a dibenzofuranyl group, and a dibenzothiophenyl group.

### Claim 11 (depends on 9)

The heterocyclic compound of claim 9, wherein
D1a and D1b are each independently a group represented by Formula 2-1:
wherein, in Formula 2-1,
c3 and c4 are each independently an integer from 1 to 4,
X1, R3, and R4, are each independently the same as described in Formula 2, and
* indicates a binding site to a neighboring atom.

### Claim 12 (depends on 9)

The heterocyclic compound of claim 9, wherein
D1a and D1b are each independently selected from groups represented by Formulae 2-2 to 2-5:
wherein, in Formulae 2-2 to 2-5,
R5 and R6 are each independently selected from hydrogen, deuterium, —F, —Cl, —Br, —I, a cyano group, a nitro group, a methyl group, an ethyl group, a propyl group, an isopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, an n-pentyl group, an isopentyl group, a sec-pentyl group, a tert-pentyl group, a neopentyl group, a hexyl group, a phenyl group, and a biphenyl group, and
* indicates a binding site to a neighboring atom.

### Claim 13

A heterocyclic compound that is selected from Compounds 1 to 39: