US008951647B2

(12) United States Patent (10) Patent No.: US 8,951,647 B2 Parham et al. (45) Date of Patent: Feb. 10, 2015

(54) ORGANICELECTROLUMINESCENCE (56) References Cited DEVICE U.S. PATENT DOCUMENTS (75) Inventors: Amir Hossain Parham, Frankfurt am 2004/0028944 A1 2/2004 Mori et al...... 428,691 Main (DE); Joachim Kaiser, Darmstadt 2004/0147742 A1* 7/2004 Wong et al. . ... 544,230 (DE); Anja Gerhard, Egelsbach (DE); 2004/01708.63 A1* 9, 2004 Kim et al...... 428,690 Jonas Valentin Kroeber, Frankfurt (DE) 2006/O115679 A1 6/2006 Chun et al. 2006/0147752 A1* 7/2006 Lee et al...... 428,690 (73) Assignee: Merck Patent GmbH, Darmstadt (DE) 2006, O199038 A1 9, 2006 Lee 2007/0051944 A1 3/2007 Vestweber et al. (*) Notice: Subject to any disclaimer, the term of this 2009,0302752 A1 12/2009 Parham et al. patent is extended or adjusted under 35 U.S.C. 154(b) by 472 days. FOREIGN PATENT DOCUMENTS (21) Appl. No.: 12/999,792 JP 2003-109767 A 4/2003 JP 2003-109768 4/2003 ...... HOSB 33/22 JP 2003-109768 A 4/2003 (22) PCT Filed: Jul. 8, 2009 JP 2006-156941 A 6, 2006 JP 2006-245565. A 9, 2006 (86). PCT No.: PCT/EP2009/004954 JP 2007-223,928 A 9, 2007 JP 2009-184987. A 8, 2009 S371 (c)(1), JP 2009-266927. A 11, 2009 (2), (4) Date: Dec. 17, 2010 WO WO-2005/053055 A1 6, 2005 WO WO-2008/086851 A1 T 2008 (87) PCT Pub. No.: WO2010/015306 OTHER PUBLICATIONS PCT Pub. Date: Feb. 11, 2010 Wu et al., Highy Bright Blue Organic Light-Emitting Devices using (65) Prior Publication Data Spirobifluorene-Cored Conjugated Compounds, 2002, Applied US 2011 FO121274 A1 May 26, 2011 Physics Letters, vol. 81, No. 4, pp. 577-579.* Wu et al., Highly bright blue organic light-emitting devices using (30) Foreign Application Priority Data spirobifluoreene-cored conjugated compounds, 2002, Applied Phys ics Letters, vol. 81, No. 4, pp. 577-579.* Aug. 8, 2008 (DE) ...... 10 2008 O36982 Shen. J.Y., et al., “High Tg blue emitting materials for electroluminescent devices.” J. Mater. Chem. 2005, vol. 15, pp. 2455 (51) Int. Cl. 2463. HOIL 5L/50 (2006.01) Lee, R.-H... et al., “Efficient fluorescent red, green, and blue organic HOIL 5L/00 (2006.01) light-emitting devices with a blue host of spirobifluorene derivative.” C09B 57/00 (2006.01) Thin Solid Films 2008, vol. 516, pp. 5062-5068. (52) U.S. Cl. CPC ...... HOIL 51/0067 (2013.01); HOIL 51/0058 * cited by examiner (2013.01); C09B 57/00 (2013.01); HOIL 5 1/5016 (2013.01); Y10S 428/917 (2013.01) Primary Examiner — Gregory Clark USPC ...... 428/690; 428/917; 313/504; 313/505; (74) Attorney, Agent, or Firm — Drinker Biddle & Reath 313/506; 257/40; 257/E51.05; 257/E51.026; LLP 257/E51.032:546/18: 546/24:546/79: 546/81; 54.6/101: 548/304.1: 548/418; 548/440: 548/444 (57) ABSTRACT (58) Field of Classification Search The present invention relates to organic electroluminescent USPC ...... 428/690,917; 313/504,505, 506; devices which comprise fluorene derivatives and spirobifluo 257/40, E51.026, E51.05, E51.032: rene derivatives as matrix material for phosphorescent emit 546/18, 24, 79, 81, 101: 544/234: ters. 548/413, 440, 304.1, 41 See application file for complete search history. 20 Claims, No Drawings US 8,951,647 B2 1. 2 ORGANICELECTROLUMNESCENCE in particular spirobifluorene derivatives, are very highly suit DEVICE able as matrix materials for phosphorescent emitters and result, in this use, in OLEDs which simultaneously have high CROSS-REFERENCE TO RELATED efficiencies, long lifetimes and low operating Voltages, APPLICATIONS including with phosphorescent emitters which contain ketoketonate ligands. This application is a national stage application (under 35 U.S. Pat. No. 6,229,012 and U.S. Pat. No. 6,225,467 dis close the use of fluorene derivatives which are substituted by U.S.C. S371) of PCT/EP2009/004954, filed Jul. 8, 2009, groups as electron-transport material in OLEDS. which claims benefit of German application 10 2008 036 However, the application does not reveal that these materials 982.9, filed Aug. 8, 2008. 10 are also suitable as matrix materials for phosphorescent emit ters. BACKGROUND OF THE INVENTION WO 05/053055 discloses the use of triazine derivatives, in particular spirobifluorene derivatives, which are substituted The present invention relates to phosphorescent organic by triazine groups as hole-blocking material in phosphores electroluminescent devices which comprise fluorene and 15 cent OLEDs. However, the application does not reveal that spirobifluorene derivatives as matrix materials. these materials are also Suitable as matrix materials for phos Organic semiconductors are being developed for a number phorescent emitters. of electronic applications of different types. The structure of organic electroluminescent devices (OLEDs) in which these BRIEF SUMMARY OF THE INVENTION organic semiconductors are employed as functional materials is described, for example, in U.S. Pat. No. 4,539,507, U.S. The invention thus relates to an organic electroluminescent Pat. No. 5,151,629, EP 0676461 and WO 98/27136. How device comprising, in at least one emitting layer, ever, further improvements are still necessary. Thus, there is (A) at least one phosphorescent compound and still a need for improvement, in particular with respect to the (B) at least one compound of the formula (1) or formula (2): lifetime, efficiency and operating Voltage of organic elec 25 troluminescent devices. It is furthermore necessary for the

compounds to have high thermal stability and a high glass formula (1) transition temperature and to be capable of sublimation with out decomposition. Especially in the case of phosphorescent electrolumines 30 cent devices, improvements in the above-mentioned proper ties are still necessary. In particular, there is a need for improvement in the case of matrix materials for phosphores cent emitters which simultaneously result in good efficiency, a long lifetime and a low operating Voltage. These very prop 35 erties of the matrix materials are frequently limiting for the lifetime and efficiency of the organic electroluminescent device. In accordance with the prior art, carbazole derivatives, for example bis-(carbazolyl)biphenyl, are frequently used as 40 where the following applies to the symbols and indices used: matrix materials. There is still a need for improvement here, Ar is on each occurrence, identically or differently, a het in particular with respect to the lifetime and glass-transition eroaryl group selected from the group consisting of triaz temperature of the materials. ine, , , , , pyrazole, Furthermore, ketones (WO 04/093207), phosphine oxides , , oxadiazole and , each of which and sulfones (WO 05/003253) are used as matrix materials 45 may be substituted by one or more groups R'; for phosphorescent emitters. Low operating Voltages and X is on each occurrence, identically or differently, a group of long lifetimes are achieved, in particular, with ketones. There is still a need for improvement here, in particular with respect the formula (3), where the dashed bond in each case indi to the efficiency and compatibility with metal complexes cates the bonding to the two rings: which contain ketoketonate ligands, for example acetylaceto 50 nate. Furthermore, metal complexes, for example BAlqor bis(2- formula (3) (2-)phenolate Zinc(II), are used as matrix YA). materials for phosphorescent emitters. There is still a need for 2 improvement here, in particular with respect to the operating 55 Voltage and the chemical stability. Purely organic compounds 2. are frequently more stable than these metal complexes. Thus, Some of these metal complexes are hydrolysis-sensitive, which makes handling of the complexes more difficult. or X is, identically or differently on each occurrence, a In particular, there is still a need for improvement in the 60 divalent bridge selected from B(R'), C(R'), Si(R'), case of matrix materials for phosphorescent emitters which C=C(R), O, S, S=O, SO, N(R'), P(R') and P(=O) simultaneously result in high efficiencies, long lifetimes and R; low operating Voltages and which are also compatible with R" is on each occurrence, identically or differently, H. D. F. phosphorescent emitters which carry ketoketonate ligands. Cl, Br, I, CHO, N(Ar), C(=O)Ar", P(=O)(Ar"), Surprisingly, it has been found that fluorene derivatives and 65 S(=O)Ar", S(=O)Ar", CR-CRAr', CN, NO, corresponding heterocyclic derivatives which are substituted Si(R), B(OR), B(R), B(N(R).), OSOR, a by triazine or other electron-deficient heterocycles, straight-chain US 8,951,647 B2 3 4 alkyl, alkoxy or thioalkoxy group having 1 to 40 Catoms or dine, pyrimidine, , etc., or a condensed aryl or het a straight-chain alkenyl or alkynyl group having 2 to 40 C eroaryl group, for example , , pyrene, atoms or a branched or cyclic alkyl, alkenyl, alkynyl, , , etc. alkoxy or thioalkoxy group having 3 to 40C atoms, each of For the purposes of this invention, an aromatic ring system which may be substituted by one or more radicals R. 5 contains at least 6 C atoms in the ring system. For the pur where one or more, preferably non-adjacent CH2 groups poses of this invention, a heteroaromatic ring system contains may be replaced by RC—CR, C=C, Si(R), Ge(R). at least2C atoms and at least 1 heteroatom in the ring system, Sn(R), C=O, C-S, C=Se, C=NR, P(=O)(R), SO, with the proviso that the sum of C atoms and heteroatoms is SO, NR’, O.S or CONR and where one or more Hatoms at least 5. The heteroatoms are preferably selected from N, O 10 and/or S. For the purposes of this invention, an aromatic or may be replaced by D. F. Cl, Br, I, CN or NO, or an heteroaromatic ring system is intended to be taken to mean a aromatic or heteroaromatic ring system having 5 to 60 system which does not necessarily contain only aryl or het aromatic ring atoms, which may in each case be substituted eroaryl groups, but instead in which a plurality of aryl or by one or more radicals R, or an aryloxy or heteroaryloxy heteroaryl groups may also be interrupted by a short non group having 5 to 60 aromatic ring atoms, which may be 15 aromatic unit (preferably less than 10% of the atoms other substituted by one or more radicals R, or a combination of than H), such as, for example, an sp- or sp-hybridised C, N these systems; two or more adjacent substituents R' here or O atom. Thus, for example, systems such as 9.9'-spirobif may also form a mono- or polycyclic, aliphatic or aromatic luorene, 9,9-diarylfluorene, triarylamine, diaryl ether, stil ring system with one another; bene, benzophenone, etc., are also intended to be taken to be Ar' is on each occurrence, identically or differently, an aro aromatic ring systems for the purposes of this invention. matic or heteroaromatic ring system having 5 to 30 aro Likewise, an aromatic or heteroaromatic ring system is taken matic ring atoms, which may be substituted by one or more to mean systems in which a plurality of aryl or heteroaryl radicals R; two radicals Ar' here which are bonded to the groups are linked to one another by single bonds, for example same nitrogen, phosphorus or boron atom may also be biphenyl, terphenyl or bipyridine. linked to one another by a single bond or a bridge selected 25 For the purposes of the present invention, a C- to Cao-alkyl from B(R), C(R), Si(R), C=O, C=NR, C=C(R), group, in which, in addition, individual H atoms or CH O, S, S=O, SO, N(R), P(R) and P(=O)R’: groups may be substituted by the above-mentioned groups, is R’ is on each occurrence, identically or differently, H, Doran particularly preferably taken to mean the radicals methyl, aliphatic, aromatic and/or heteroaromatic hydrocarbon ethyl, n-propyl, i-propyl. n-butyl, i-butyl, S-butyl, t-butyl, 30 2-methylbutyl, n-pentyl, S-pentyl, tert-pentyl, 2-pentyl, radical having 1 to 20 C atoms, in which, in addition, H cyclopentyl, n-hexyl, S-hexyl, t-hexyl, 2-hexyl, 3-hexyl, atoms may be replaced by D or F: two or more adjacent cyclohexyl, 2-methylpentyl, n-heptyl, 2-heptyl, 3-heptyl, Substituents Rhere may also form a mono- or polycyclic, 4-heptyl, cycloheptyl, 1-methylcyclohexyl, n-octyl, 2-ethyl aliphatic or aromatic ring system with one another; hexyl, cyclooctyl, 1-bicyclo2.2.2]octyl, 2-bicyclo[2.2.2]oc n is 0 or 1; 35 tyl, 2-(2,6-dimethyl)octyl, 3-(3,7-dimethyl)octyl, trifluorom m is 0, 1, 2 or 3: ethyl, pentafluoroethyl, 2.2.2-trifluoroethyl, ethenyl, o is 0, 1, 2, 3 or 4 if n=0 and is 0, 1, 2 or 3 if n=1. propenyl, butenyl, pentenyl, cyclopentenyl, hexenyl, cyclo hexenyl, heptenyl, cycloheptenyl, octenyl, cyclooctenyl, DETAILED DESCRIPTION OF THE INVENTION ethynyl, propynyl, butynyl, pentynyl, hexynyl, heptynyl or 40 octynyl. A C- to Co-alkoxy group is particularly preferably An organic electroluminescent device is taken to mean a taken to mean methoxy, trifluoromethoxy, ethoxy, n-propoxy, device which comprises anode, cathode and at least one emit i-propoxy, n-butoxy, i-butoxy, S-butoxy, t-butoxy or 2-meth ting layer which is arranged between the anode and the cath ylbutoxy. An aromatic or heteroaromatic ring system having ode, where at least one layer between the anode and cathode 5-60 aromatic ring atoms, which may also in each case be comprises at least one organic or organometallic compound. 45 substituted by the radicals R mentioned above and may be At least one emitting layer here comprises at least one phos linked to the aromatic or heteroaromatic group via any phorescent emitter and at least one compound of the above desired positions, is taken to mean, in particular, groups mentioned formula (1) or (2). An organic electroluminescent derived from benzene, naphthalene, anthracene, phenan device does not necessarily have to comprise only layers built threne, benzanthracene, pyrene, chrysene, perylene, fluoran up from organic or organometallic materials. Thus, it is also 50 thene, benzofluoranthene, naphthacene, pentacene, benzopy possible for one or more layers to comprise inorganic mate rene, biphenyl, biphenylene, terphenyl, terphenylene, rials or to be built up entirely from inorganic materials. fluorene, benzofluorene, dibenzofluorene, spirobifluorene, For the purposes of this invention, a phosphorescent com dihydrophenanthrene, dihydropyrene, tetrahydropyrene, cis pound is a compound which exhibits luminescence from an or trans-indenofluorene, cis- or trans-monobenzoindenofluo excited State of relatively high spin multiplicity, i.e. a spin 55 rene, cis- or trans-dibenzoindenofluorene, truxene, isotruX state-1, in particular from an excited triplet state, at room ene, spirotruXene, spiroisotruXene, , , temperature. For the purposes of this invention, all lumines , dibenzofuran, thiophene, , cent iridium and platinum compounds, in particular, are to be isobenzothiophene, dibenzothiophene, , , isoin regarded as phosphorescent compounds. dole, carbazole, pyridine, quinoline, isoquinoline, acridine, For the purposes of this invention, an aryl group contains at 60 phenanthridine, benzo-5,6-quinoline, benzo-6,7-quinoline, least 6 C atoms; for the purposes of this invention, a het benzo-7,8-quinoline, phenothiazine, phenoxazine, pyrazole, eroaryl group contains at least 2 C atoms and at least 1 , imidazole, , naphthimidazole, heteroatom, with the proviso that the sum of C atoms and phenanthrimidazole, pyridimidazole, pyrazinimidazole, qui heteroatoms is at least 5. The heteroatoms are preferably noxalinimidazole, oxazole, , naphthoxazole, selected from N, O and/or S. An aryl group or heteroaryl 65 anthroxazole, phenanthroxazole, isoxazole, 1,2-thiazole, 1.3- group here is taken to mean either a simple aromatic ring, i.e. thiazole, benzothiazole, pyridazine, benzopyridazine, pyri benzene, or a simple heteroaromatic ring, for example pyri midine, benzopyrimidine, , 1,5-diazaanthracene, US 8,951,647 B2 5 6 2,7-diazapyrene, 2,3-diazapyrene, 1,6-diazapyrene, 1,8-di where the symbols and indices used have the same meanings azapyrene, 4.5-diazapyrene, 4.5.9,10-tetraazaperylene, pyra as described above. Zine, phenazine, phenoxazine, phenothiazine, fluorubin, The group Ar represents an electron-deficient heteroaro naphthyridine, azacarbazole, benzocarboline, phenanthro matic group. The group Ar preferably stands, identically or line, 1,2,3-triazole, 1,2,4-triazole, benzotriazole, 1.2.3-oxa differently on each occurrence, for a 6-membered heteroaro diazole, 1,2,4-oxadiazole, 1,2,5-oxadiazole, 1.3,4-oxadiaz matic ring, i.e. for triazine, pyrazine, pyrimidine, pyridazine ole, 1,2,3-thiadiazole, 1,2,4-thiadiazole, 1,2,5-thiadiazole, or pyridine, each of which may be substituted by one or more 1,3,4-thiadiazole, 1,3,5-triazine, 1,2,4-triazine, 1,2,3-triaz radicals R'. ine, , 1,2,4,5-, 1,2,3,4-tetrazine, 1.2.3,5-tet razine, , pteridine, indolizine and benzothiadiazole. 10 In a preferred embodiment of the invention, the monova The compounds of the formulae (1) and (2) preferably have lent group Arin compounds of the formulae (1), (2) and (4) to a glass-transition temperature T of greater than 70° C., par (7) is selected from the groups of the following formulae (8) ticularly preferably greater than 90° C., very particularly to (20), where the dashed bond in each case indicates the bonding of the group to the fluorene or spirobifluorene or to preferably greater than 110° C. 15 In a preferred embodiment of the invention, the group X the corresponding heterocyclic derivative, and R' has the stands, identically or differently on each occurrence, for a same meaning as described above: group of the formula (3) or for a divalent bridge selected from C(R'), Si(R'), and NR'. In a particularly preferred embodi formula (8) ment of the invention, the group X stands for a group of the RI formula (3) or for C(R). The compound of the formula (1) is thus particularly pref / N erably either a spirobifluorene derivative if the group Xstands for a group of the formula (3) or a fluorene derivative if the y group X stands for C(R'). Likewise, the compound of the 25 )=N formula (2) is particularly preferably a spirobifluorene RI derivative, a fluorene derivative or a compound which con formula (9) tains a spirobifluorene group and a fluorene group. The fluo R1 rene derivatives of the formulae (4) and (5) and the spirobif N luorene derivatives of the formulae (6) and (7) are therefore a 30 particularly preferred embodiment of the invention: RI / y NFN formula (10) R1

formula (4) 35 ^y -N\,.... V NR RI 40 formula (11) R1 N R-( \ 45 NRN formula (12) R1 R1

50 ( \,... NRN formula (13) R1 RI 55 / \. V NR RI formula (14) 60 RI

65 US 8,951,647 B2 7 8 -continued -continued formula (15) formula (22) RI R1 N R-( \ y NR NRN formula (23) RI R1 RI formula (16) 10 R1 N NRN R-4 y formula (24) w RI RN 15 R1 formula (17) / \. RI )=N N R1 formula (25) R-/ \. RI FN R1 25 formula (18) ( ) R1 RI NR RI formula (26) R-/ \,... RI 30 RN R1 ; V formula (19) RN R1 RI 35 R1 formula (27) ( \,... R1 R1 NR RI M \,... 40 formula (20) =N R1 RI formula (28) R1 RI 45

R1 sRI RN

In a preferred embodiment of the invention, the divalent 50 group Arin compounds of the formulae (2) and (7) is selected from the groups of the following formulae (21) to (28), where In a preferred embodiment of the invention, the group Ar the dashed bonds in each case indicate the bonding of the contains two or three nitrogen atoms. Preferred monovalent group to the fluorene or spirobifluorene or the corresponding groups Arare therefore the groups of the formulae (8) to (17), 55 and preferred divalent groups Arare the groups of the formu heterocyclic derivative, and R' has the same meaning as lae (21) to (26). The group Arparticularly preferably contains described above: three nitrogen atoms. Particularly preferred monovalent groups Arare therefore the groups of the formulae (8) to (11), in particular the group of the formula (8), and particularly formula (21) 60 preferred divalent groups Arare the groups of the formulae R1 (21) and (22), in particular the group of the formula (21). In a further preferred embodiment of the invention, the X radical R' which is bonded to the groups of the formulae (8) to (28) stands, identically or differently on each occurrence, 65 for H. D., a straight-chain alkyl oralkoxy group having 1 to 10 A. f( ). C atoms or a branched or cyclic alkyl oralkoxy group having 3 to 10 C atoms, each of which may be substituted by one or US 8,951,647 B2 9 10 more radicals R, where one or more H atoms may be -continued replaced by D or F, or an aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms, which may in each formula (30) case be substituted by one or more radicals R, or a combi nation of these systems. In a particularly preferred embodi ment of the invention, the radical R' which is bonded to the groups of the formulae (8) to (28) stands, identically or dif ferently on each occurrence, for H or D, a straight-chain alkyl group having 1 to 5 C atoms or a branched or cyclic alkyl group having 3 to 6 C atoms, each of which may be substi tuted by one or more radicals R, where one or more H atoms may be replaced by D or F, or for an aromatic or heteroaro matic ring system having 5 to 25 aromatic ring atoms, which may in each case be substituted by one or more radicals R. or a combination of these systems. The radical R' which is bonded to the groups of the formulae (8) to (28) very particu larly preferably stands, identically or differently on each occurrence, for H or D or for an aromatic or heteroaromatic ring system having 5 to 14 aromatic ring atoms, which may in each case be substituted by one or more radicals R in par ticular for phenyl, naphthyl or biphenyl, each of which may be substituted by one or more radicals R, but is preferably unsubstituted. In a further preferred embodiment of the invention, the 25 formula (32)

radical R' which is bonded directly to the fluorene or spiro bifluorene or the corresponding stands, identically or differently on each occurrence, for H, a straight-chain alkyl oralkoxy group having 1 to 10C atoms or 30 a branched or cyclic alkyl or alkoxy group having 3 to 10C atoms, each of which may be substituted by one or more radicals R, where one or more H atoms may be replaced by D or F, oran aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms, which may in each case be substi 35 tuted by one or more radicals R, or a combination of these systems. In a particularly preferred embodiment of the inven tion, the radical R' which is bonded directly to the fluorene or spirobifluorene or the corresponding heterocyclic compound stands, identically or differently on each occurrence, for H, a 40 straight-chain alkyl group having 1 to 5 Catoms or a branched where the symbols and indices have the same meaning as or cyclic alkyl group having 3 to 6 C atoms, each of which described above, and where, for n=0, a substituent R' may may be substituted by one or more radicals R, where one or also be bonded in the corresponding position. A preferred more H atoms may be replaced by D or F, or for an aromatic or heteroaromatic ring system having 5 to 25 aromatic ring 45 embodiment of the compounds of the formulae (29) and (30) atoms, which may in each case be substituted by one or more are compounds in which X stands for C(R'). radicals R. In a preferred embodiment of compounds of the formulae (1), (2), (4) to (7) and (29) to (32), the index m=0, i.e. no In a further preferred embodiment of the invention, the further substituent apart from the group Ar is bonded to this group Aris bonded in the 2-position of the fluorene or spiro 50 bifluorene or of the corresponding heterocycle. If more than benzene ring. one group Ar is present, the other groups Arare preferably In a further preferred embodiment of compounds of the bonded in the 7-position and, in spirobifluorene derivatives, formulae (1), (2), (4) to (7) and (29) to (32), the sum of the also in the 2'-position and 7'-position. Particularly preferred indices n+o-0 or 1 on each benzene ring, i.e. a maximum of compounds of the formulae (1), (2) and (4) to (7) are therefore 55 one group Ar or a maximum of one radical R' is bonded to the compounds of the formulae (29) to (32): each benzene ring. Preferred embodiments of the compounds of the formulae (29) to (32) are compounds in which the group Arstands for a group of the formulae (8) to (28) indicated above. formula (29) 60 X In a very particularly preferred embodiment of the inven tion, the group Ar in the compounds of the formulae (29) to A-\ \ Y-1A pi (32) stands for a group of the formula (8) or formula (21). Sis 2. Furthermore particularly preferably in these compounds, R 65 m=0 and n+o-0 or 1 on each benzene ring. Very particular R. preference is therefore given to the compounds of the formu lae (33) to (36): US 8,951,647 B2 11 12

formula (33)

formula (34) X -, (Y-SA 2\ R formula (35)

formula (36)

50 where the symbols and indices used have the meanings men tioned above, and furthermore n+o=0 or 1 on each benzene ring and where, for n=0 and o=1, the radical R' may be bonded to any desired free site on the benzene ring. Preferred 55 formula (37) embodiments of compounds of the formulae (33) and (34) are those in which X stands for C(R'). Particular preference is given to the spirobifluorene deriva- 60 tives of the formulae (35) and (36), in particular the spirobi fluorene derivative of the formula (35). The compounds of the formula (35) very particularly preferably contain one or two triazine groups. The compounds of the formula (35) are thus 65 particularly preferably selected from compounds of the for mulae (37), (38) and (39): US 8,951,647 B2 13 14 -continued -continued formula (38) (3)

- R1 N QSO e N f 10 N COO) f

15

(4) formula (39)

where the symbols used have the meanings mentioned above ando Stands, identically or differently on each occurrence, for N f 0 or 1. N N O O Examples of preferred compounds of the formulae (1), (2), * Y-C) below.(4) to (7) and (29) to (39) are structures (1) to (96) depicted leN O Ne 40 (1) NJ r OSO *C) C

NJ-, CO S.- (2) 55 (7) \ | (N

s 60 x-ON C O \ -N a ry-QUON-N C Na eN N- a () N f COO 65 NJ- CS ON | N O, OO CO CO . e COO N , OSO | h COO c - ototry C US 8,951,647 B2 17 18 o P 2. COO ... r. COO OO Cy C sc COO 3: Ol-k N

US 8,951,647 B2 19 20

COO O | OSO \ O C, CO QC COO

Q ry-O SO O " (, eN 2. O OO O C CO US 8,951,647 B2 21 22 , OO C-O-C c COO O

US 8,951,647 B2 25 26 -continued -continued (46) (50) O-O-O --OO CS C CO Coo 'sage:336 338 is o, OSO s

Y-Q-C) 45 c (y- 27 28 -continued -continued (54) (58) Q N O 5 Y N O O N| NN OO N d leN C 10

') 33, 40 goes 61 X O 50 c (62) N " * -O soon-)-CC, a C-9/Oloo C, CO So ... O O

US 8,951,647 B2 33 34

(82)

(83) 35 US 8,951,647 B2 35 36 -continued -continued (89) (93) F F

5 N N | N | N N N leN leN

(94) F

15

N

F (90) N| N C F leN 2O F

F | | N C 25 N leN F (95) D

F D 30 F D F N

F ! N Y-Q-C) 35 leN (91) D () D

D N 40 D | N D N (96) leN F

45 N N Y-K) leN F 50 F (92) D D D 55 The compounds of the formula (1) can be synthesised, for D example, by the processes described in U.S. Pat. No. 6,229. N 012, U.S. Pat. No. 6,225,467 and WO 051053055. In general, N metal-catalysed coupling reactions are suitable for the Syn D d thesis of the compounds, in particular the Suzuki coupling, as leN shown in Scheme 1 below for the example of the triazine. 60 Thus, a fluorene, spirobifluorene or other heterocyclic deriva D tive, each of which is substituted by a boronic acid or a D boronic acid derivative, can be coupled with palladium catalysis to the group Ar which is Substituted by one reactive D leaving group for compounds of the formula (1) and by two D 65 reactive leaving groups for compounds of the formula (2). D Suitable reactive leaving groups are, for example, halogens, in particular chlorine, bromine and iodine, triflate or tosylate. US 8,951,647 B2 37 38

Scheme 1: 1. C Air Ar’-B(OH)i l 2els N11. NN N11. NN Ar 1 N Air Ar-MgBr + us es2 -- us els2 C N C C N Air

r Ar = aryl or heteroaryl group Ar' = spirobifluorene or fluorene

As described above, the compounds of the formulae (1) via which the cyclic group is bonded to the metal and which and (2) are used as matrix materials for phosphorescent emit may in turn carry one or more substituents R'; the groups terS. DCy and CCy are bonded to one another via a covalent Suitable phosphorescent compounds are, in particular, bond; compounds which emit light, preferably in the visible region, CCy is, identically or differently on each occurrence, a cyclic on Suitable excitation and in addition contain at least one atom group which contains a atom via which the cyclic having an atomic number of greater than 20, preferably group is bonded to the metal and which may in turn carry greater than 38 and less than 84, particularly preferably one or more substituents R'; greater than 56 and less than 80. The phosphorescence emit A is, identically or differently on each occurrence, a monoan ters used are preferably compounds which contain copper, ionic, bidentate chelating ligand, preferably a diketonate molybdenum, tungsten, rhenium, ruthenium, osmium, ligand. rhodium, iridium, palladium, platinum, silver, gold or A bridge may also be present between the groups DCy and europium, in particular compounds which contain iridium or CCy due to the formation of ring systems between a plurality platinum. of radicals R'. Particularly preferred organic electroluminescent devices Examples of the emitters described above are revealed by comprise, as phosphorescent emitters, at least one compound the applications WO 00/70655, WO 01/41512, WO of the formulae (40) to (43): 02/02714, WO 02/15645, EP 1191613, EP 1191612, EP 1191614 and WO 05/033244. In general, all phosphorescent formula (40) complexes as are used in accordance with the prior art for DCy phosphorescent OLEDs and as are known to the person A-Ir skilled in the art in the area of organic electroluminescence CC y 2 are suitable, and the person skilled in the art will be able to use formula (41) further phosphorescent complexes without inventive step. DCy Apart from the cathode, anode and one or more emitting Ir layers, the organic electroluminescent device may also com CCy 3 prise further layers. These are selected, for example, from in formula (42) each case one or more hole-injection layers, hole-transport DCy layers, hole-blocking layers, electron-transport layers, elec A-PC tron-injection layers, electron-blocking layers, exciton CCy blocking layers, charge-generation layers (IDMC 2003, Tai formula (43) DCy wan; Session 21 OLED (5), T. Matsumoto, T. Nakada, J. Pt Endo, K. Mori, N. Kawamura, A.Yokoi, J. Kido, Multiphoton CCy Organic EL Device Having Charge Generation Layer) and/or 2 organic or inorganic pin junctions. In addition, interlayers which control the charge balance in the device may be where R' has the same meaning as described above for for present. Furthermore, the layers, in particular the charge mulae (1) and (2), and the following applies to the other transport layers, may also be doped. The doping of the layers symbols used: may be advantageous for improved charge transport. How DCy is, identically or differently on each occurrence, a cyclic ever, it should be pointed out that each of these layers does not group which contains at least one donor atom, preferably necessarily have to be present and the choice of layers is nitrogen, carbon in the form of a carbene or phosphorus, always dependent on the compounds used. US 8,951,647 B2 39 40 In a further preferred embodiment of the invention, the materials are vapour-deposited in vacuum Sublimation units organic electroluminescent device comprises a plurality of at an initial pressure of less than 10 mbar, preferably less emitting layers, where at least one emitting layer comprises at than 10 mbar. However, it should be noted that the pressure least one compound of the formula (1) or formula (2) and at may also be even lower, for example less than 107 mbar. least one phosphorescent emitter. These emission layers par Preference is likewise given to an organic electrolumines ticularly preferably have in total a plurality of emission cent device, characterised in that one or more layers are maxima between 380 nm and 750 nm, resulting overall in applied by means of the OVPD (organic vapour phase depo white emission, i.e. various emitting compounds which are sition) process or with the aid of carrier-gas Sublimation, in able to fluoresce or phosphoresce and which emit blue and which the materials are applied at a pressure between 10 yellow, orange or red light are used in the emitting layers. 10 mbar and 1 bar. A special case of this process is the OVJP Particular preference is given to three-layer systems, i.e. sys (organic vapour jet printing) process, in which the materials tems having three emitting layers, where at least one of these are applied directly through a nozzle and thus structured (for layers comprises at least one compound of the formula (1) or example M. S. Arnold et al., Appl. Phys. Lett. 2008, 92, formula (2) and at least one phosphorescent emitter and 053301). where the three layers exhibit blue, green and orange or red 15 Preference is furthermore given to an organic electrolumi emission (for the basic structure, see, for example, WO nescent device, characterised in that one or more layers are 05/011013). The use of more than three emitting layers may produced from Solution, such as, for example, by spin coat also be preferred. Likewise suitable for white emission are ing, or by means of any desired printing process, such as, for emitters which have broad-band emission bands and thus example, Screen printing, flexographic printing or offset exhibit white emission. printing, but particularly preferably LITI (light induced ther The emitting layer which comprises the mixture of the mal imaging, thermal transfer printing) or ink-jet printing. compound of the formula (1) or formula (2) and the phospho Soluble compounds are necessary for this purpose. High solu rescent emitter preferably comprises between 99 and 50% by bility can be achieved through suitable substitution of the vol., preferably between 98 and 50% by vol., particularly compounds. Not only solutions of individual materials, but preferably between 97 and 60% by vol., in particular between 25 also solutions comprising a plurality of compounds, for 95 and 85% by vol., of the compound of the formula (1) or example matrix materials and dopants, can be applied here. formula (2), based on the entire mixture of emitter and matrix The organic electroluminescent device can also be pro material. Correspondingly, the mixture comprises between 1 duced as a hybrid system by applying one or more layers from and 50% by vol., preferably between 2 and 50% by vol., Solution and vapour-depositing one or more other layers. particularly preferably between 3 and 40% by vol., in particu 30 Thus, for example, it is possible to apply an emitting layer lar between 5 and 15% by vol., of the phosphorescent emitter, comprising a compound of the formula (1) or (2) and a phos based on the entire mixture of emitter and matrix material. phorescent dopant from solution and to apply a hole-blocking Preference is furthermore also given to the use of a plural layer and/or an electron-transport layer on top by vacuum ity of matrix materials as a mixture, where one matrix mate vapour deposition. The emitting layer comprising a com rial is selected from compounds of the formula (1) or (2). The 35 pound of the formula (1) or (2) and a phosphorescent dopant compounds of the formula (1) and formula (2) have predomi can likewise be applied by vacuum vapour deposition and one nantly electron-transporting properties due to the electron or more other layers can be applied from Solution. deficient nitrogen heterocycles Ar. If a mixture oftwo or more These processes are generally known to the person skilled matrix materials is used, a further component of the mixture in the art and can be applied by him without problems to is therefore preferably a hole-transporting compound. Pre 40 organic electroluminescent devices comprising compounds ferred hole-conducting matrix materials are triarylamines, of the formula (1) or (2) or the preferred embodiments men carbazole derivatives, for example CBP (N.N-biscarbazolyl tioned above. biphenyl) or the carbazole derivatives disclosed in WO The present invention furthermore relates to mixtures com 05/039246, US 2005/0069729, JP 2004/288381, EP 1205527 prising at least one phosphorescent emitter and at least one or WO 08/086,851, azacarbazoles, for example inaccordance 45 compound of the formula (1) or formula (2). with EP 1617710, EP 1617711, EP 1731584, JP 2005/ The invention furthermore relates to Solutions comprising 347160, bipolar matrix materials, for example in accordance a mixture of at least one phosphorescent emitter and at least with WO 07/137,725, and 9,9-diarylfluorene derivatives, for one compound of the formula (1) or formula (2) and at least example in accordance with the unpublished application DE one organic solvent. 102008017591.9. The mixture of matrix materials may also 50 The present invention still furthermore relates to the use of comprise more than two matrix materials. It is furthermore compounds of the formula (1) or formula (2) as matrix mate also possible to use the matrix material of the formula (1) or rial for phosphorescent emitters in an organic electrolumines formula (2) as a mixture with a further electron-transporting cent device. matrix material. Preferred further electron-transporting The organic electroluminescent devices according to the matrix materials are ketones, for example in accordance with 55 invention have the following Surprising advantages over the WO 04/093207, tetraaryl ketones, for example in accordance prior art: with DE 102008033943.1, phosphine oxides, sulfoxides and 1. The organic electroluminescent devices according to the sulfones, for example in accordance with WO 05/003253, invention have very high efficiency. oligophenylenes, bipolar matrix materials, for example in 2. The organic electroluminescent devices according to the accordance with WO 07/137,725, silanes, for example in 60 invention simultaneously have an improved lifetime. accordance with WO 05/11 1172.9,9-diarylfluorene deriva 3. The organic electroluminescent devices according to the tives (for example in accordance with the unpublished appli invention simultaneously have a reduced operating Volt cation DE 102008017591.9), azaboroles or boronic esters age. (for example in accordance with WO 06/117052). 4. The above-mentioned improved properties of the organic Preference is furthermore given to an organic electrolumi 65 electroluminescent devices are obtained not only with tris nescent device, characterised in that one or more layers are ortho-metallated metal complexes, but, in particular, also applied by means of a Sublimation process, in which the with complexes which also contain a ketoketonate ligand, US 8,951,647 B2 41 42 for example acetylacetonate. In particular for complexes of The synthesis is carried out analogously to Example 1, with this type, matrix materials in accordance with the prior art the 2.7'-di-tert-butylspiro-9.9'-bifluorene-2.7-bis(boronic are still in need of improvement with respect to the effi acid glycol ester) being replaced by 22.8 g (50 mmol) of ciency, lifetime and operating Voltage. spiro-9.9'-bifluorene-2.7-bis(boronic acid glycol ester). The The invention is described in greater detail by the following 5 yield is 32.3 g (41.5 mmol), corresponding to 82.9% of examples, without wishing to restrict it thereby. The person theory. skilled in the art will be able, without an inventive step, to prepare further compounds according to the invention and use them in organic electronic devices. Example 3 EXAMPLES 10 Synthesis of 2-(4,6-diphenyl-1,3,5-triazin-2-yl)spiro The following syntheses are carried out under a protective 9,9'-bifluorene (TRIAZINE3) gas atmosphere in dried solvents, unless indicated otherwise. The starting materials can be purchased from ALDRICH (potassium fluoride (spray-dried), tri-tert-butylphosphine, palladium(II) acetate). 3-Chloro-5,6-diphenyl-1,2,4-triazine 15 can be prepared analogously to EP 577559. 2',7-Di-tert-bu tylspiro-9.9'-bifluorene-2.7-bisboronic acid glycol ester can be prepared in accordance with WOO2/077060 and 2-chloro 4,6-diphenyl-1,3,5-triazine in accordance with U.S. Pat. No. 5,438,138. Spiro-9.9'-bifluorene-2.7-bis(boronic acid glycol ester) can be prepared analogously to WO 02/077060. Example 1 Synthesis of 2.7-bis(4,6-diphenyl-1,3,5-triazin-2-yl)- 2',7'-di-tert-butylspiro-9.9'-bifluorene (TRIAZINE 1) 25

a) Synthesis of spiro-9.9'-bifluorene-2-boronic acid

30 73.7 ml (184 mmol) of n-butyllithium (2.5 M in hexane) are added dropwise to a solution, cooled to -78°C., of 71 g (180 mmol) of 2-bromo-9-spirobifluorene in 950 ml of diethyl ether. The reaction mixture is stirred at -78° C. for min. The mixture is allowed to come to room temperature and 35 is recooled to -78°C., and a mixture of 26.4 ml (234 mmol) of trimethyl borate in 50 ml of diethyl ether is then added rapidly. After warming to -10°C., the mixture is hydrolysed 28.4 g (50.0 mmol) of 2,7'-di-tert-butylspiro-9.9'-bifluo using 90 ml of 2 N hydrochloric acid. The organic phase is rene-2.7-bisboronic acid glycol ester, 29.5 g (110.0 mmol) of separated off, washed with water, dried over sodium sulfate 2-chloro-4,6-diphenyl-1,3,5-triazine and 44.6 g (210.0 40 mmol) of tripotassium phosphate are suspended in 500 ml of and evaporated to dryness. The residue is taken up in 200 ml toluene, 500 ml of dioxane and 500 ml of water. 913 mg (3.0 of n-heptane, and the colourless solid is filtered off with mmol) of tri-o-tolylphosphine and then 112 mg (0.5 mmol) of suction, washed with n-heptane and dried in vacuo. Yield: 63 palladium(II) acetate are added to this suspension, and the g (170 mmol), 98% of theory; purity: 98% according to reaction mixture is heated under reflux for 16 h. After cooling, H-NMR. the organic phase is separated off, filtered through silica gel. 45 washed three times with 200 ml of water and subsequently b) Synthesis of 2-(4,6-diphenyl-1,3,5-triazin-2-yl) evaporated to dryness. The residue is recrystallised from tolu spiro-9.9'-bifluorene ene and from dichloromethanefisopropanol and finally Sub limed in a high vacuum (p=5x10-5 mbar, T-385°C.). The yield is 39.9 g (44.8 mmol), corresponding to 89.5% of 50 The synthesis is carried out analogously to Example 1, with theory. the 2.7'-di-tert-butylspiro-9.9'-bifluorene-2.7-bis(boronic acid glycol ester) being replaced by 28 g (50 mmol) of spiro Example 2 9.9'-bifluorene-2-boronic acid. The yield is 38 g (41.5 mmol), Synthesis of 2.7-bis(4,6-diphenyl-1,3,5-triazin-2-yl) corresponding to 95.0% of theory. spiro-9.9'-bifluorene (TRIAZINE2) Example 4 Production and Characterisation of Organic Electroluminescent Devices Comprising Triazine 60 Compounds Electroluminescent devices according to the invention can O-O-O-, ZN be produced as described, for example, in WO 05/003253. The results for various OLEDs are compared here. The basic COO 65 structure, the materials used, the degree of doping and the layer thicknesses thereof are identical for better comparabil ity. US 8,951,647 B2 43 44 Examples 5-7, 12 and 15 describe comparative standards in -continued accordance with the prior art, in which the emission layer consists of the host material (or matrix material) bis(9.9'- spirobifluoren-2-yl) ketone (SK) or BAlqor a 50:50 SK:CBP mixture and various guest materials (dopants) TER for red or 5 TEG for green triplet emission. Furthermore, OLEDs which comprise the fluorenetriazine derivatives or spirobifluoren etriazine derivatives as host material are described. OLEDs having the following structure are produced analogously to the general process mentioned above: 10 Hole-injection layer (HIL) 20 nm of 2,2,7,7-tetrakis(di-para spiroketone (SK) tolylamino)spiro-9.9'-bifluorene Hole-transport layer (HTL) 20 nm of NPB (N-naphthyl-N- phenyl-4,4'-diaminobiphenyl) 15 Emission layer (EML) 40 nm of host material: spiroketone (SK) (bis(9.9'-spirobifluoren-2-yl) ketone) or BAlq ((1,1'- biphenyl-4'-oxy)bis(8-hydroxy-2-methylduinolinato)alu minium) or SK and CBP (4,4'-bis(carbazol-9-yl)biphenyl) mixed in equal proportions as comparison or compounds according to the invention. Dopant: 15% by Vol. doping; compounds see below Hole-blocking layer (HBL) 10 nm of SK (optional) Electron conductor (ETL) 20 nm of AlQ (tris(quinolinato) aluminium(III)) 25 Cathode 1 nm of LiF 100 nm of Al on top. The structures of TER-1, TER-2, TEG, SK, BAlq, CBP are shown below for clarity.

30 Sc.BAlq

35

N 40 O OR

2 Pt 21 NN \ 21 45 C C N N TER-1 TER-2 CB 50 Coa. The TRIAZINE2 and TRIAZINE3 used have the structures depicted above in Examples 2 and 3. These as yet unoptimised OLEDs are characterised by 55 standard methods; for this purpose, the electroluminescence spectra, the efficiency (measured in cd/A) as a function of the luminance, the operating Voltage, calculated from current Voltage-luminance characteristic lines (IUL characteristic HC leN Ir lines), and the lifetime are determined. 60 As can be seen from Tables 1 and 3, the devices exhibit superior behaviour in the efficiencies, voltages and lifetimes measured compared with the comparative devices compris ing the host materials SK or BAlq. Furthermore, Table 2 65 shows that TRIAZINE2 and TRIAZINE3 are very highly TEG Suitable for forming a mixed host with carbazole-containing host materials (here CBP). US 8,951,647 B2 45 46 TABLE 1.

Device results with TRIAZINE2 and TRIAZINE3 in combination with TER-1 or TER-2 as dopant Max. eff. Lifetime h, EML colf A at Voltage IV CIE initial luminance Ex. (no HBL) 1000 ccd/m2 at 1000 ccd/m? (x,y) 1000 ccd/m? S SKi:TER-1 S.6 4.9 0.690.31 3OOO comp. 6 BAlq:TER-1 7.0 6.2 0.690.31 8SOO comp. 7 SKi:TER-2 6.8 S.6 0.66.O.33 14OOO comp. 8 TRLAZINE2:TER-1 7.5 4.8 0.680.32 18OOO 9 TRIAZINE3:TER-1 7.2 S.O 0.690.31 14OOO 10 TRIAZINE2:TER-2 9.8 6.5 0.66.O.33 21OOO 11 TRIAZINE3:TER-2 9.O 6.5 0.66.O.33 18OOO

TABLE 2

Device results with TRIAZINE2 and TRIAZINE3 in combination with CBP and with TER-1 or TER-2 as dopant Max. eff. Voltage IV Lifetime h, initial EML colf A at at 1.OOO CIE luminance 1000 Ex. (with HBL) 1000 ccd/m? cal/m? (x,y) cd/m? 12 SKCBP:TER-1 7.2 5.2 0.680.32 7000 comp. 13 TRIAZINE2:CBP:TER-1 8.O 4.7 0.680.32 2SOOO 14 TRIAZINE3:CBP:TER-1 8.1 5.2 0.680.32 1SOOO

TABLE 3 where the following applies to the symbols and indices used: Ar is on each occurrence, identically or differently, a het Device results with TRIAZINE3 in combination with TEG as dopant eroaryl group selected from the group consisting of tri 35 azine, pyrazine, pyridazine, pyridine, pyrazole, imida Max. Lifetime Zole, oxazole and thiazole, each of which may be eff Voltage h, initial cd/A) at V at luminance substituted by one or more groups R'; EML 1OOO 1OOO CIE 1OOO X is on each occurrence, identically or differently, a group Ex. (with HBL) cal/m? cal/m? (x,y) cal/m? of the formula (3), where the dashed bond in each case 40 1S SKi:TEG 27 4.2 0.360.61 1OOOO indicates the bonding to the two benzene rings: comp. 16 TRIAZINE3:TEG 35 4.7 0.360.61 2SOOO formula (3) s 45 YArl, The invention claimed is: 1. An organic electroluminescent device comprising, in at least one emitting layer, 2. (A) at least one phosphorescent compound and 50 (B) at least one compound of the formula (1) or formula or X is on each occurrence, identically or differently, a diva (2): lent bridge selected from B(R'), C(R), Si(R'), C=C(R'), O, S, S=O, SO, N(R'), P(R') and P(=O)R'; R" is on each occurrence, identically or differently, H. D. F. formula (1) 55 Cl, Br, I, CHO, N(Ar), C(=O)Ar", P(=O)(Ar"), S(=O)Ar", S(=O)Ar", CR-CRAr', CN, NO, Si(R), B(OR), B(R), B(N(R).), OSOR, a straight-chain alkyl, alkoxy or thioalkoxy group having 1 to 40 C atoms or a straight-chain alkenyl or alkynyl formula (2) 60 group having 2 to 40 C atoms or a branched or cyclic alkyl, alkenyl, alkynyl, alkoxy or thioalkoxy group hav ing 3 to 40 C atoms, each of which is optionally substi "Y-y-'l'-ry." tuted by one or more radicals R, where one or more, non-adjacent CH2 groups is optionally replaced by irSpi Cl C. Arl, 65 R°C–CR, C=C, Si(R), Ge(R), Sn(R), C=O, C-S, C-Se, C-NR, P(=O)(R), SO, SO, NR, O, S or CONR and where one or more H atoms is option US 8,951,647 B2 47 48 ally replaced by D, F, Cl, Br, I, CN or NO, or an -continued aromatic or heteroaromatic ring system having 5 to 60 formula (7)

aromatic ring atoms, which is optionally in each case be substituted by one or more radicals R, or an aryloxy or heteroaryloxy group having 5 to 60 aromatic ring atoms, which is optionally substituted by one or more radicals R’, or a combination of these systems; two or more adjacent substituents R' here may also form a mono- or polycyclic, aliphatic or aromatic ring system with one another, Ar' is on each occurrence, identically or differently, an aromatic or heteroaromatic ring system having 5 to 30 where the symbols and indices used have the same meanings aromatic ring atoms, which is optionally Substituted by as described in claim 1. one or more radicals R; two radicals Ar" here which are 15 bonded to the same nitrogen, phosphorus or boronatom 3. The organic electroluminescent device according to are optionally linked to one another by a single bond or claim 2, wherein the monovalent group Aris selected from the a bridge selected from the group consisting of B(R), groups of the formulae (8) to (20), where the dashed bond in each case indicates the bonding of the group to the fluorene or C(R), Si(R), C=O, C=NR, C=C(R), O, S, spirobifluorene or to the corresponding heterocyclic deriva S—O, SO, N(R), P(R) and P(O)R’; tive, and R' has the same meaning as described in claim 2, and R’ is on each occurrence, identically or differently, H. Dor in that the divalent group Ar in compounds of the formulae an aliphatic, aromatic and/or heteroaromatic hydrocar (2), (5) and (7) is selected from the groups of the formulae bon radical having 1 to 20 Catoms, in which, in addition, (21) to (28), where the dashed bonds in each case indicate the H atoms is optionally replaced by D or F: two or more 25 bonding of the group to the fluorene or spirobifluorene or to adjacent substituents Rhere optionally form amono- or the corresponding heterocyclic derivative, and R' has the polycyclic, aliphatic or aromatic ring system with one same meaning as described in claim 2: another, n is 0 or 1; 30 m is 0, 1, 2 or 3: formula (8) o is 0, 1, 2, 3 or 4 if n=0 and is 0, 1, 2 or 3 if n=1. R 2. The organic electroluminescent device according to )- claim 1, wherein the compound of the formula (1) or formula / y (2) is a fluorene derivative of the formula (4) or formula (5) or 35 )=N a spirobifluorene derivative of the formula (6) or formula (7): RI

formula (4) 40 formula (9) R R-/ Ny 45 NRN formula (10) R

50 )-/ \. V NR RI formula (11) 55 R N formula (6) R1 ( \. NRN 60 formula (12) R R ( \,... 65 US 8,951,647 B2 49 50 -continued -continued formula (13) formula (21) R1 RI / \. V NR RI formula (22) 10

formula (14) R1 RI NRN 15 formula (23) / \. R1 RI )=N R1 formula (15) NFN RI formula (24) N w RI RI ( \. NF 25 RI )=N formula (16) R1 R1 formula (25) RI 30 d \ R1 NR RI formula (17) 35 formula (26) RI RI R-(N \,... ; V RN 40 RN R1 R1 formula (18) formula (27) R1 RI R1 R1 / \,... 45 / \,... FN =N R1 formula (28) 50 R1 R1 formula (19) R1 RI

55 RN M \,... R1 NF 4. The organic electroluminescent device according to RI claim3, wherein the radical R' which is bonded to the groups formula (20) of the formulae (8) to (28) stands, identically or differently on R1 RI 60 each occurrence, for H or D, a straight-chain alkyl or alkoxy group having 1 to 10C atoms or a branched or cyclic alkyl or alkoxy group having 3 to 10 C atoms, each of which is / \. optionally substituted by one or more radicals R. Where one or more H atoms is optionally replaced by D or F, or an 65 aromatic or heteroaromatic ring system having 5 to 30 aro R1 RI matic ring atoms, which may in each case be substituted by one or more radicals R, or a combination of these systems. US 8,951,647 B2 51 52 5. The organic electroluminescent device according to -continued claim 2, wherein the compound of the formula (1), (2) or (4) formula (32) to (5) is selected from compounds of the formulae (29) to (32): formula (29) X

sfs lea R iii. Y. Cs formula (30) 10

15 kforinula (31) where the symbols and indices have the same meaning as described in claim 2, and where, for n=0, a substituent R' may also be bonded in the corresponding position.

6. The organic electroluminescent device according to 25 claim 1, wherein the index m=0 and in that the sum of the indices n+o-0 or 1 on each benzene ring. 7. The organic electroluminescent device according to claim 1, wherein the compound of the formula (1) or formula (2) is selected from compounds of the formulae (33) to (36):

formula (33)

formula (34) US 8,951,647 B2 53 54 -continued formula (35)

formula (36)

where the symbols and indices used have the meanings men -continued tioned in claim 1, and furthermore n+o=0 or 1 on each ben 35 formula (39) Zene ring and where, for n=0 and o=1, the radical R' may be bonded to any desired free site on the benzene ring. 8. The organic electroluminescent device according to claim 7, wherein the compounds of the formula (35) are selected from compounds of the formulae (37), (38) and (39): 40

formula (37) 45

50 where the symbols used have the meanings mentioned above ando Stands, identically or differently on each occurrence, for 0 or 1.

formula (38) 55

9. The organic electroluminescent device according to claim 1, wherein the phosphorescent compound is a com pound which contains copper, molybdenum, tungsten, rhe nium, ruthenium, osmium, rhodium, iridium, palladium, platinum, silver, gold or europium. 10. The organic electroluminescent device according to claim 1, wherein the phosphorescent compound is a com pound which contains iridium or platinum. 65 11. The organic electroluminescent device according to claim 10, wherein the phosphorescent compound is selected from compounds of the formulae (40) to (43): US 8,951,647 B2 56

formula (40) formula (1) DCy A-Ir CC y 2 formula (41) DCy Ir formula (2) CCy 3 formula (42) DCy 10 "y-ry-'l', ry." A-PC CCy CSC OS formula (43) DCy Pt 15 CCy where the following applies to the symbols and indices used 2 Ar is on each occurrence, identical or differently, a het eroaryl group selected from the group consisting of tri where R' has the same meaning as described in claim 10, and azine, pyrazine, pyridazine, pyridine, pyrazole, imida the following applies to the other symbols used: Zole, oxazole, and thiazole, each of which may be DCy is, identically or differently on each occurrence, a substituted by one or more groups R'; cyclic group which contains at least one donoratom and X is on each occurrence, identically or differently, a group which optionally carries one or more substituents R; the of the formula (3), where the dashed bond in each case groups DCy and CCy are bonded to one another via a indicates the bonding to the two benzene rings: covalent bond; 25 CCy is, identically or differently on each occurrence, a cyclic group which contains a carbonatom via which the formula (3) cyclic group is bonded to the metal and which may in |Arl. turn carry one or more substituents R'; and 2) A is, identically or differently on each occurrence, a 30 monoanionic, bidentate chelating ligand. 2. 12. The organic electroluminescent device according to claim 11, wherein DCy is, identically or differently on each occurrence, a or X is on each occurrence, identically or differently, a diva cyclic group which contains at nitrogen, carbon in the 35 lent bridge selected from B(R'), C(R), Si(R'), C=C(R'), form of a carbene or phosphorus, via which the cyclic O, S, S=O, SO, N(R'), P(R') and P(=O)R'; group is bonded to the metal and which optionally car R" is on each occurrence, identically or differently, H. D. F. ries one or more substituents R'; the groups DCy and Cl, Br, I, CHO, N(Ar), C(=O)Ar", P(=O)(Ar"), CCy are bonded to one another via a covalent bond; and S(=O)Ar", S(=O)Ar", CR-CRAr', CN, NO, A is, identically or differently on each occurrence, a dike 40 Si(R), B(OR), B(R), B(N(R).), OSOR, a tonate ligand. straight-chain alkyl, alkoxy or thioalkoxy group having 13. The organic electroluminescent device according to 1 to 40 C atoms or a straight-chain alkenyl or alkynyl claim 1, which comprises an anode, a cathode and at least one group having 2 to 40 C atoms or a branched or cyclic emitting layer, and further layers selected from in each case alkyl, alkenyl, alkynyl, alkoxy or thioalkoxy group hav one or more hole-injection layers, hole-transport layers, hole 45 ing 3 to 40 C atoms, each of which is optionally substi blocking layers, electron-transport layers, electron-injection tuted by one or more radicals R, where one or more, layers, electron-blocking layers, excitor-blocking layers, non-adjacent CH groups is optionally replaced by charge-generation layers, interlayers and/or organic or inor R°C–CR, C=C, Si(R), Ge(R), Sn(R), C=O, ganic pfnjunctions, where the layers are optionally doped. C—S, C-Se, C-NR, P(=O)(R), SO, SONR, O, 14. The organic electroluminescent device according to 50 S or CONR and where one or more H atoms is option claim 2, wherein the emitting layer, in addition to the phos ally replaced by D, F, Cl, Br, I, CN or NO, or an phorescent compound and the compound of the formula (1) aromatic or heteroaromatic ring system having 5 to 60 or (2), also comprises one or more further compounds. aromatic ring atoms, which is optionally in each case be 15. The organic electroluminescent device according to substituted by one or more radicals R, or an aryloxy or claim 3, wherein the one or more further compounds are 55 heteroaryloxy group having 5 to 60 aromatic ring atoms, selected from the group consisting of triarylamines, carba which is optionally substituted by one or more radicals Zole derivatives, azacarbazoles and bipolar matrix materials. R’, or a combination of these systems; two or more 16. A process for the production of the organic electrolu adjacent substituents R' here may also form a mono- or minescent device according to claim 4, wherein one or more polycyclic, aliphatic or aromatic ring system with one layers are produced by means of a Sublimation process, by 60 another, means of the OVPD (organic vapour phase deposition) pro Ar" is on each occurrence, identically or differently, an cess, with the aid of carrier-gas Sublimation, by means of the aromatic or heteroaromatic ring system having 5 to 30 OVJP (organic vapour jet printing) process, from Solution or aromatic ring atoms, which is optionally Substituted by by means of a printing process. one or more radicals R; two radicals Ar" here which are 17. A matrix material for phosphorescent compounds in an 65 bonded to the same nitrogen, phosphorus or boronatom organic electroluminescent device which comprises the com are optionally linked to one another by a single bond or pounds of the formula (1) and (2) a bridge selected from the group consisting of B(R), US 8,951,647 B2 57 58 C(R), Si(R), C-O, C-NR, C=C(R), O, S, aromatic ring atoms, which is optionally in each case be S—O, SO, N(R), P(R) and P(=O)R’: substituted by one or more radicals R, or an aryloxy or R’ is on each occurrence, identically or differently, H. Dor heteroaryloxy group having 5 to 60 aromatic ring atoms, an aliphatic, aromatic and/or heteroaromatic hydrocar which is optionally substituted by one or more radicals bon radical having 1 to 20 Catoms, in which, in addition, R°, or a combination of these systems; two or more H atoms is optionally replaced by D or F: two or more adjacent substituents R' here may also form a mono- or adjacent substituents Rhere optionally form amono- or polycyclic, aliphatic or aromatic ring system with one polycyclic, aliphatic or aromatic ring system with one another, another, Ar' is on each occurrence, identically or differently, an n is 0 or 1; 10 aromatic or heteroaromatic ring system having 5 to 30 m is 0, 1, or 3: aromatic ring atoms, which is optionally Substituted by o is 0, 1, 2, 3 or 4 if n=0 and is 0, 1, 2 or 3 if n=1. one or more radicals R; two radicals Ar" here which are 18. A mixture comprising at least one compound of the bonded to the same nitrogen, phosphorus or boronatom formula (1) or (2) are optionally linked to one another by a single bond or 15 a bridge selected from the group consisting of B(R), C(R), Si(R), C-O, C-NR, C=C(R), O, S, formula (1) S—O, SO, N(R), P(R) and P(O)R’; R’ is on each occurrence, identically or differently, H. Dor an aliphatic, aromatic and/or heteroaromatic hydrocar bon radical having 1 to 20 Catoms, in which, in addition, H atoms is optionally replaced by D or F: two or more adjacent substituents Rhere optionally form amono- or formula (2) polycyclic, aliphatic or aromatic ring system with one another, R x 25 s"). X s". n is 0 or 1; Y () m is 0, 1, 2 or 3: o is 0, 1, 2, 3 or 4 if n=0 and is 0, 1, 2 or 3 if n=1; Ar h(S SC; Arl, and at least one phosphorescent compound. 19. A Solution comprising the mixture according to claim where the following applies to the symbols and indices used: 30 18 and at least one organic solvent. Ar is on each occurrence, identical or differently, a het 20. The organic electroluminescent, device according to eroaryl group selected from the group consisting of tri claim 4, wherein the phosphorescent compound is selected azine, pyrazine, pyridazine, pyridine, pyrazole, imida from compounds of the formulae (40) to (43): Zole, oxazole, and thiazole, each of which may be substituted by one or more groups R'; 35 X is on each occurrence, identically or differently, a group formula (40) of the formula (3), where the dashed bond in each case indicates the bonding to the two benzene rings: 40 formula (41) formula (3) YA). 2) formula (42) 2. 45 formula (43) or X is on each occurrence, identically or differently, a diva lent bridge selected from B(R'), C(R), Si(R'), C=C(R'), 50 O, S, S=O, SO, N(R'), P(R') and P(=O)R'; R" is on each occurrence, identically or differently, H. D. F. Cl, Br, I, CHO, N(Ar), C(=O)Ar", P(=O)(Ar"), wherein S(=O)Ar", S(=O)Ar", CR-CRAr', CN, NO, DCy is, identically or differently on each occurrence, a Si(R), B(OR), B(R), B(N(R).), OSOR, a 55 cyclic group which contains at least one donoratom and straight-chain alkyl, alkoxy or thioalkoxy group having which optionally carries one or more substituents R; the 1 to 40 C atoms or a straight-chain alkenyl or alkynyl groups DCy and CCy are bonded to one another via a group having 2 to 40 C atoms or a branched or cyclic covalent bond; alkyl, alkenyl, alkynyl, alkoxy or thioalkoxy group hav CCy is, identically or differently on each occurrence, a ing 3 to 40 C atoms, each of which is optionally substi 60 cyclic group which contains a carbonatom via which the tuted by one or more radicals R, where one or more, cyclic group is bonded to the metal and which may in non-adjacent CH2 groups is optionally replaced by turn carry one or more substituents R'; R°C—C, C=C, Si(R), Ge(R), Sn(R), C=O, A is, identically or differently on each occurrence, a C-S, C-Se, C–NR, P(=O)(R), SO, SO, NR, O, monoanionic, bidentate chelating ligand; S or CONR and where one or more H atoms is option 65 R" is on each occurrence, identically or differently, H. D. F. ally replaced by D, F, Cl, Br, I, CN or NO, or an Cl, Br, I, CHO, N(Ar), C(=O)Ar", P(=O)(Ar), aromatic or heteroaromatic ring system having 5 to 60 S(=O)Ar", S(=O)Ar", CR-CRAr', CN, NO, US 8,951,647 B2 59 60 Si(R), B(OR), B(R), B(N(R).), OSOR, a here may also form a mono- or polycyclic, aliphatic or Straight-chain alkyl, alkoxy or thioalkoxy group having aromatic ring system with one another; 1 to 40 C atoms or a straight-chain alkenyl or alkynyl Ar' is on each occurrence, identically or differently, an group having 2 to 40 C atoms or a branched or cyclic aromatic or heteroaromatic ring system having 5 to 30 aromatic ring atoms, which is optionally substituted by alkyl, alkenyl, alkynyl, alkoxy or thioalkoxy group hav one or more radicals R; two radicals Ar' here which are ing 3 to 40 Catoms, each of which is optionally substi bonded to the same nitrogen, phosphorus or boronatom tuted by one or more radicals R, where one or more, are optionally linked to one another by a single bond or non-adjacent CH groups is optionally replaced by a bridge selected from the group consisting of B(R), R°C—CR, Ge(R), Sn(R), C-O, C-S, C-Se, C(R), Si(R), C=O, C-NR, C. C(R), O, S, C=NR, P(=O)(R), SO, SO, NR, O, S or CONR 10 S—O, SO, N(R), P(R) and P(=O)R’; and and where one or more Hatoms is optionally replaced by R’ is on each occurrence, identically or differently, H, Dor D. F. Cl, Br, I, CN or NO, or an aromatic or heteroaro an aliphatic, aromatic and/or heteroaromatic hydrocar matic ring system having 5 to 60 aromatic ring atoms, bon radical having 1 to 20 Catoms, in which, in addition, which is optionally in each case be substituted by one or H atoms is optionally replaced by D or F: two or more more radicals R. or an aryloxy or heteroaryloxy group 15 adjacent substituents Rhere optionally form a mono- or having 5 to 60 aromatic ring atoms, which is optionally polycyclic, aliphatic or aromatic ring system with one substituted by one or more radicals R, or a combination another. of these systems; two or more adjacent substituents R'