Phenoxasiline based compounds for electronic application

Abstract

Organic electronics applications, especially an organic light-emitting diode (OLED), an organic solar cell (organic photovoltaics) or a switching element such as an organic transistor, for example an organic FET (Field Effect Transistor) and an organic TFT (Thin Film Transistor), comprising at least one substituted phenoxasiline derivative, a organic semiconductor layer, a host material, electron/hole/exciton blocking material or electron/hole injection material comprising at least one substituted phenoxasiline derivative, the use of a substituted phenoxasiline derivative in organic electronics applications, an organic light-emitting diode, wherein at least one substituted phenoxasiline derivative is present in the electron/hole/exciton blocking layer, the electron/hole injection layer and/or the light-emitting layer, a light-emitting layer, an electron/hole/exciton blocking layer and an electron/hole injection layer comprising at least one substituted phenoxasiline derivative and a device selected from the group consisting of stationary visual display units, mobile visual display units; illumination units; keyboards; garments; furniture and wallpaper comprising at least one organic light-emitting diode, at least one light-emitting layer, at least one electron/hole/exciton blocking layer and/or at least one electron/hole injection layer according to the present invention.

Claims

1. A compound of the formula (I) ##STR00040## in which R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6 and R.sup.7 are each independently hydrogen, C.sub.1-C.sub.20-alkyl, C.sub.3-C.sub.20-cycloalkyl, heterocycloalkyl having 3 to 20 ring atoms, C.sub.6-C.sub.30-aryl, heteroaryl having 5 to 30 ring atoms or a substituent with donor or acceptor action selected from the group consisting of C.sub.1-C.sub.20-alkoxy, C.sub.6-C.sub.30-aryloxy, C.sub.1-C.sub.20-alkylthio, C.sub.6-C.sub.30-arylthio, SiR.sup.10R.sup.11R.sup.12, halogen radicals, halogenated C.sub.1-C.sub.20-alkyl radicals, carbonyl (—CO(R.sup.10)), carbonylthio (—C═O(SR.sup.10)), carbonyloxy (—C═O(OR.sup.10)), oxycarbonyl (—OC═O(R.sup.10)), thiocarbonyl (—SC═O(R.sup.10)), amino (—NR.sup.10R.sup.11), OH, pseudohalogen radicals, amido (—C═O(NR.sup.10R.sup.11)), —NR.sup.10C═O(R.sup.11), phosphonate (—P(O) (OR.sup.10).sub.2), phosphate (—OP(O)(OR.sup.10).sub.2), phosphine (—PR.sup.10R.sup.11), phosphine oxide (—P(O)R.sup.10.sub.2), sulfate (—OS(O).sub.2OR.sup.10), sulfoxide (—S(O)R.sup.10), sulfonate (—S(O).sub.2OR.sup.10), sulfonyl (—S(O).sub.2R.sup.10), sulfonamide (—S(O).sub.2NR.sup.10R.sup.11), NO.sub.2, boronic esters (—OB(OR.sup.10).sub.2), imino (—C═NR.sup.10), borane radicals, stannane radicals, hydrazine radicals, hydrazone radicals, oxime radicals, nitroso groups, diazo groups, vinyl groups, sulfoximines, alanes, germanes, boroxines and borazines; or two adjacent R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6 or R.sup.7 radicals, in each case together with the carbon atoms to which they are bonded, form a ring having a total of 3 to 12 atoms, where the ring is saturated or mono- or polyunsaturated and, as well as carbon atoms, has or does not have one or more heteroatoms selected from N, O and P, where the ring is unsubstituted or mono- or polysubstituted and/or is fused to further 3- to 12-membered rings; R.sup.8 and R.sup.9 are each independently C.sub.1-C.sub.20-alkyl, C.sub.3-C.sub.20-cycloalkyl, heterocycloalkyl having 3 to 20 ring atoms, C.sub.6-C.sub.30-aryl or heteroaryl having 5 to 30 ring atoms; R.sup.10, R.sup.11, R.sup.12 are each independently C.sub.1-C.sub.20-alkyl, C.sub.3-C.sub.20-cycloalkyl, heterocycloalkyl having 3 to 20 ring atoms, C.sub.6-C.sub.30-aryl, heteroaryl having 5 to 30 ring atoms, —O—Si(C.sub.1-C.sub.20-alkyl).sub.3, —O—Si(C.sub.6-C.sub.30-aryl).sub.3, C.sub.1-C.sub.20-alkoxy or C.sub.6-C.sub.30-aryloxy; or two adjacent R.sup.10 and R.sup.11, R.sup.10 and R.sup.12 or R.sup.11 and R.sup.12 radicals, together with the atom to which they are bonded, form a ring having a total of 3 to 12 atoms, where the ring is saturated or mono- or polyunsaturated and, as well as the atom to which the R.sup.10, R.sup.11 or R.sup.12 radicals are bonded, have exclusively carbon atoms or one or more further heteroatoms selected from N, O and P, where the ring is unsubstituted or mono- or polysubstituted and/or is fused to further 3- to 12-membered rings; with the proviso that for —NR.sup.10C═O(R.sup.11), the two adjacent R.sup.10 and R.sup.11 radicals, together with the atom to which they are bonded, form a ring having a total of 3 to 12 atoms, where the ring is saturated or mono- or polyunsaturated and, as well as the atom to which the R.sup.10 or R.sup.11 radicals are bonded, have exclusively carbon atoms or one or more further heteroatoms selected from N, O and P, where the ring is unsubstituted and/or is fused to further unsubstituted 3- to 12-membered rings; Y is C.sub.3-C.sub.20-alkyl, C.sub.3-C.sub.20-cycloalkyl, heterocycloalkyl having 3 to 20 ring atoms, C.sub.6-C.sub.30-aryl, heteroaryl having 5 to 30 ring atoms or a substituent with donor or acceptor action selected from the group consisting of C.sub.1-C.sub.20-alkoxy, C.sub.6-C.sub.30-aryloxy, C.sub.1-C.sub.20-alkylthio, C.sub.6-C.sub.30-arylthio, SiR.sup.10R.sup.11R.sup.12, halogen radicals, halogenated C.sub.1-C.sub.20-alkyl radicals, carbonyl(—CO(R.sup.10)), carbonylthio (—C═O(SR.sup.10)), carbonyloxy (—C═O(OR.sup.10)), oxycarbonyl (—OC═O(R.sup.10)), thiocarbonyl (—SC═O(R.sup.10)), amino (—NR.sup.10R.sup.11), OH, pseudohalogen radicals, amido (—C═O (NR.sup.10R.sup.11)), —NR.sup.10C═O(R.sup.11), phosphonate (—P(O)(OR.sup.10).sub.2), phosphate (—OP(O)(OR.sup.10).sub.2), phosphine (—PR.sup.10R.sup.11), phosphine oxide (—P(O)R.sup.10.sub.2), sulfate (—OS(O).sub.2OR.sup.10), sulfoxide (—S(O)R.sup.10), sulfonate (—S(O).sub.2OR.sup.10), sulfonyl (—S(O).sub.2R.sup.10), sulfonamide (—S(O).sub.2NR.sup.10R.sup.11), NO.sub.2, boronic esters (—OB(OR.sup.10).sup.2), imino (—C═NR.sup.10), borane radicals, stannane radicals, hydrazine radicals, hydrazone radicals, oxime radicals, nitroso groups, diazo groups, vinyl groups, sulfoximines, alanes, germanes, boroxines and borazines; or SiR.sup.10R.sup.11R.sup.12.

2. The compound according to claim 1, wherein Y is heteroaryl having 5 to 30 ring atoms selected from the group consisting of pyrrolyl, furanyl, thienyl, benzoanellated ring systems of pyrrolyl, furanyl, thienyl, pyridyl, pyrimidyl, pyrazolyl, imidazolyl, thiazolyl, oxazolyl, triazoly and phenanthrolinyl; or SiR.sup.10R.sup.11R.sup.12.

3. The compound according to claim 2 wherein the benzoanellated ring systems of pyrrolyl, furanyl, thienyl are selected from benzofuranyl, benzothienyl, indolyl, isoindolyl, isoindolizinyl, carbazolyl, aza-carbazolyl, diazacarbazolyl, dibenzofuryl, dibenzothienyl.

4. The compound according to claim 1, wherein Y is heteroaryl having 5 to 30 ring atoms selected from the group consisting of pyrrolyl, furanyl, thienyl, benzoanellated ring systems of pyrrolyl, furanyl, thienyl, pyridyl, pyrimidyl, pyrazolyl, imidazolyl, thiazolyl, oxazolyl, triazoly and phenanthrolinyl; or SiR.sup.10R.sup.11R.sup.12; and R.sup.10, R.sup.11 and R.sup.12 are each independently C.sub.6-C.sub.30-aryl.

5. The compound according to claim 4, wherein Y is selected from the group consisting of pyrrolyl, furanyl, thienyl, benzofuranyl, benzothienyl, indolyl, isoindolyl, isoindolixinyl, carbazolyl, azacarbazolyl, diazacarbazolyl, dibenzofuryl, dibenzothienyl, and SiPh.sub.3.

6. The compound according to claim 4, wherein the benzoanellated ring systems of pyrrolyl, furanyl, thienyl are selected from benzofuranyl, benzothienyl, indolyl, isoindolyl, isoindolizinyl, carbazolyl, aza-carbazolyl, diazacarbazolyl, dibenzofuryl, dibenzothienyl.

7. The compound according to claim 1, wherein Y is selected from the group consisting of ##STR00041## and SiPh.sub.3, wherein X is NR.sup.10, O or S, R.sup.10 is C.sub.1-C.sub.20-alkyl, C.sub.3-C.sub.20-cycloalkyl, heterocycloalkyl having 3 to 20 ring atoms, C.sub.6-C.sub.30-aryl, heteroaryl having 5 to 30 ring atoms, —O—Si(C.sub.1-C.sub.20-alkyl).sub.3, —O—Si(C.sub.6-C.sub.30-aryl).sub.3, C.sub.1-C.sub.20-alkoxy or C.sub.6-C.sub.30-aryloxy; and R.sup.13 is H or phenoxasilinyl of formula (I′) ##STR00042## wherein the substituents Y′, R.sup.1′, R.sup.2′, R.sup.3′, R.sup.4′, R.sup.5′, R.sup.7′, R.sup.8′ and R.sup.9′ have independently the same meanings as the substituents Y, R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.7, R.sup.8 and R.sup.9 in the phenoxasiline derivatives of formula (I), and the symbol ˜ means that there is a binding site at the position marked with ˜.

8. The compound according to claim 1, wherein R.sup.8 and R.sup.9 are each independently C.sub.6-C.sub.30-aryl or heteroaryl having 5 to 30 ring atoms.

9. The compound according to claim 8, wherein the compound of formula (I) is selected from the compounds of formulae (Ia), (Ib), (Ic) and (Id) ##STR00043## Wherein Y and R.sup.6 are each independently heteroaryl having 5 to 30 ring atoms selected from the group consisting of pyrrolyl, furanyl, thienyl, benzoanellated ring systems of pyrrolyl, furanyl, thienyl, pyridyl, pyrimidyl, pyrazolyl, imidazolyl, thiazolyl, oxazolyl, triazoly and phenanthrolinyl; or SiR.sup.10R.sup.11R.sup.12; R.sup.3 and R.sup.4 are each independently C.sub.1-C.sub.20-alkyl, C.sub.3-C.sub.20-cycloalkyl, heterocycloalkyl having 3 to 20 ring atoms, C.sub.6-C.sub.30-aryl, heteroaryl having 5 to 30 ring atoms, methoxy, phenyloxy, halogenated C.sub.1-C.sub.4-alkyl, or halogen, and R.sup.10, R.sup.11 and R.sup.12 are each independently C.sub.6-C.sub.30-aryl, and R.sup.8 and R.sup.9 are each independently C.sub.6-C.sub.30-aryl or heteroaryl having 5 to 30 ring atoms.

10. The compound according to claim 9 wherein the benzoanellated ring systems of pyrrolyl, furanyl, thienyl are selected from benzofuranyl, benzothienyl, indolyl, isoindolyl, isoindolizinyl, carbazolyl, aza-carbazolyl, diazacarbazolyl, dibenzofuryl, dibenzothienyl.

11. The compound according to claim 1, wherein R.sup.8 and R.sup.9 are identical.

12. The compound according to claim 1, wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, R.sup.6 and R.sup.7 are each hydrogen or R.sup.1, R.sup.2, R.sup.5, R.sup.6 and R.sup.7 are each hydrogen and R.sup.3 and R.sup.4 are each independently C.sub.1-C.sub.20-alkyl, C.sub.3-C.sub.20-cycloalkyl, heterocycloalkyl having 3 to 20 ring atoms, C.sub.6-C.sub.30-aryl, heteroaryl having 5 to 30 ring atoms, methoxy, phenyloxy, halogenated C.sub.1-C.sub.4-alkyl, halogen, CN, SiR.sup.10R.sup.11R.sup.12, P(O)Ph.sub.2 or diphenylamino.

13. The compound according to claim 1, wherein R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5, and R.sup.7 are hydrogen, and R.sup.6 is heteroaryl having 5 to 30 ring atoms selected from the group consisting of pyrrolyl, furanyl, thienyl, benzoanellated ring systems of pyrrolyl, furanyl, thienyl, pyridyl, pyrimidyl, pyrazolyl, imidazolyl, thiazolyl, oxazolyl, triazoly and phenanthrolinyl; or SiR.sup.10R.sup.11R.sup.12; and R.sup.10, R.sup.11 and R.sup.12 are each independently C.sub.6-C.sub.30-aryl.

14. The compound according to claim 13, wherein the benzoanellated ring systems of pyrrolyl, furanyl, thienyl are selected from benzofuranyl, benzothienyl, indolyl, isoindolyl, isoindolizinyl, carbazolyl, aza-carbazolyl, diazacarbazolyl, dibenzofuryl, dibenzothienyl.

Description

EXAMPLES

I Synthesis Examples

I.1 Preparation of the Building Block 2,8-Dibromo-10,10-diphenyl-phenoxasilane (PXBr)

(1) i) Preparation of 2,2′,4,4′-Tetrabromodiphenylether

(2) ##STR00029##

(3) A mixture of diphenyl ether (5.0 g, 29.5 mmol), iron powder (0.1 g, 1.79 mmol) and carbon tetrachloride (50 ml) is heated to 70° C. for 24 hr. To the mixture is added bromine (19.3 g, 120.9 mmol) in carbon tetrachloride (50 ml) keeping the temperature at 75° C. for 1 hour. Then to the reaction mixture is added chloroform (40 ml), then, filtered, and washed with water. The organic layer is separated, and evaporated to dryness. The resulting solid is purified by recrystallization from n-hexane to afford a colorless solid (10.6 g, 74.3%).

(4) .sup.1H-NMR (400 MHz, CDCl.sub.3): δ 7.79 (d, J=2.28 Hz, 2H), 7.38 (dd, J=2.3 Hz, 2H), 6.71 (d, J=8.7 Hz, 2H), 7.39-7.24 (m, 30H) ppm.

(5) EIMS (m/z)=486 [M.sup.+].

(6) ii) Preparation of 2,8-Dibromo-10,10-Diphenyl-Phenoxasilane (PXBr)

(7) ##STR00030##

(8) To a round bottom flask is added 2,2′,4,4′-tetrabromodiphenylether (3.0 g, 6.176 mmol). After nitrogen flow for 1 hour, dry diethyl ether (30 ml) is added. The resultant mixture is cooled to −10° C. in an ice bath (dry ice/acetone) then n-butyllithium (1.6 M, 8.0 ml) is added dropwise. After stirring for 2 hours at room temperature, the mixture is cooled to −70° C. and dichlorodiphenylsilane (1.6 g, 6.36 mmol) is added dropwise. The resultant mixture is stirred for 19 hours at room temperature, and precipitate is filtered. The organic layer is washed with water, the mixture is separated, and dried over anhydrous MgSO.sub.4. Then, the mixture is filtered, and evaporated to dryness, then, purified by chromatography on silica gel (eluent: hexane/toluene=4/1) to afford PXBr (2.1 g, 69.0%)

(9) .sup.1H-NMR (400 MHz, CD.sub.2Cl.sub.2): δ 7.61-7.53 (m, 8H), 7.49-7.38 (m, 6H), 7.18 (d, J=8.7 Hz, 2H) ppm

(10) EIMS (m/z)=508 [M.sup.+].

I.2 Synthesis of Compound (1)

(11) ##STR00031##

(12) To a round bottom flask is added PXBr (synthesis example I.1) (2.00 g, 3.93 mmol) carbazole (1.38 g, 8.25 mmol), and sodium-tert-butoxide (1.13 g, 11.8 mmol). Dry xylene (80 ml) is added and nitrogen bubbled through the mixture for 1 hour. Then, Pd(OAc).sub.2 (17.6 mg, 79.6 μmol), tritert-butylphosphine (73.8.Math.l, 0.314 mmol) are added and the resultant mixture is vigorously stirred for 5 hours at reflux temperature under N.sub.2 flow. The resulting mixture is cooled to room temperature. The precipitate is filtered, and washed with water. The organic layer is separated and dried over anhydrous MgSO.sub.4, filtered, and evaporated. The resulting mixture is filtered through silica gel pad (eluent: toluene). The filtrate is evaporated to dryness, poured into hexane to afford a white solid (2.07 g:77.4 g).

(13) .sup.1H-NMR: (400 MHz, CD.sub.2Cl.sub.2): δ 8.14 (d, J=8.0 Hz, 4H), 7.80 (d, J=2.8 Hz, 2H), 7.75 (q, J=8.8 Hz, 2H), 7.67-7.60 (m, 6H), 7.47-7.37 (m, 14H), 7.30-7.26 (m, 4H) ppm.

(14) EIMS (m/z)=681[M.sup.+]

(15) Anal, Calcd for C.sub.48H.sub.32N.sub.2OSi: C, 84.67; H, 4.74; N, 4.11%. Found: C, 84.77; H, 4.55; N, 4.11%.

I.3 Synthesis of Compound (2)

(16) ##STR00032##

(17) To a round bottom flask is added PXBr (synthesis example I.1) (3.00 g, 5.90 mmol). After nitrogen flow for 1.5 hour, dry tetrahydrofuran (60 ml) is added. The resultant mixture is cooled to −70° C., then n-butyllithium (1.6 M, 11.1 ml) is added dropwise. After stirring for 1 hour at −70° C., ether solution (20 ml) of triphenychlorolsilane (5.21 g, 17.7 mmol) is added dropwise. The resultant mixture is stirred at room temperature. The reaction mixture is evaporated, dissolved in toluene (80 ml) and washed with water. The organic layer is separated and dried over anhydrous MgSO.sub.4, filtered, and evaporated to dryness. The resulting solid is purified by recrystallization from toluene to afford a white solid. (2.88 g, 56.3%)

(18) .sup.1H-NMR (400 MHz, THF-d.sub.4): δ 7.96 (s, 2H), 7.62 (d, J=8.2 Hz, 2H), 7.51 (d, J=8.2 Hz, 12H), 7.39-7.24 (m, 30H) ppm,

(19) EIMS (m/z)=868 [M.sup.+],

(20) Anal, Calcd for C.sub.60H.sub.46OSi.sub.3: C, 83.09; H, 5.35%. Found: C, 83.04; H, 5.28%.

I.4 Synthesis of Compound (3)

(21) ##STR00033##

(22) To a round bottom flask is added PXBr (synthesis example I.1) (2.00 g, 3.93 mmol) and dibenzofuran-4-boronic acid (2.43 g, 8.25 mmol). To the mixture are added toluene (40.0 ml), ethanol (20.0 ml) and aqueous Na.sub.2CO.sub.3 (2.6 M, 11.8 ml) and nitrogen bubbles through the mixture for 1 hour. Then, Pd(PPh).sub.4 (0.23 g, 0.20 mmol) is added and the resultant mixture is vigorously stirred for 12 hours at reflux temperature under N.sub.2 flow. The resulting mixture is cooled to room temperature. The precipitate is filtered, and dissolved in reflux toluene (200 ml), filtered through a silica-gel pad. The clear filtrate is evaporated to dryness. The resulting white solid is further purified by recrystallization from toluene (1.45 g, 54%).

(23) 1H-NMR (400 MHz, CD2Cl2): δ 8.12 (d, J=2.0 Hz, 2H), 8.01 (d, J=7.6 Hz, 2H), 7.86-7.81 (m, 4H), 7.71-7.56 (m, 10H), 7.49-7.34 (m, 12H) ppm.

(24) EIMS (m/z)=683[M.sup.+]

(25) Anal, Calcd for C.sub.48H.sub.32N.sub.2OSi: C, 84.43; H, 4.43%. Found: C, 84.37; H, 4.21%.

I.5 Synthesis of Compounds (4), (5) and (6)

(26) ##STR00034## ##STR00035##

(27) Compounds (4), (5) and (6) are prepared in analogy to compounds (1), (2) and (3), whereby the correct stoichiometry is to be applied.

I.6 Synthesis of Compound (V7)

(28) ##STR00036##

(29) Compound (V7) is disclosed in JP2006083167 (CZNTPH).

II Diode Examples

II. 1 Production of an OLED Comprising Compound (1) as Host Material and Hole Blocker Material (OLED (1))

(30) The ITO substrate used as the anode is first cleaned with commercial detergents for LCD production (Deconex® 20NS and 25ORGAN-ACID® neutralizing agent) and then in an acetone/isopropanol mixture in an ultrasound bath. To eliminate possible organic residues, the substrate is exposed to a continuous ozone flow in an ozone oven for a further 25 minutes. This treatment also improves the hole injection properties of the ITO. Next, the AJ20-1000 hole injection layer from Plexcore is spun on from solution (˜40 nm).

(31) Thereafter, the organic materials specified below are applied to the cleaned substrate by vapor deposition at a rate of approx. 0.5-5 nm/min at about 10.sup.−8 mbar. The hole conductor and exciton blocker applied to the substrate is Ir(dpbic).sub.3 (V1) (DPBIC) with a thickness of 35 nm doped with MoO.sub.3 (˜50% by weight) to improve the conductivity.

(32) ##STR00037## disclosed, for example, in WO2005/019373

(33) Subsequently, Ir(dpbic).sub.3 (V1) is applied by vapor deposition in a thickness of 5 nm.

(34) Subsequently, a mixture of Emitter (E1) (30% by weight), Ir(dpbic).sub.3 (V1) (host H1) (15% by weight) and compound (1) (synthesis example I.2) (host H2) (55% by weight) are applied by vapor deposition in a thickness of 40 nm the former compound functioning as an emitter material, the two latter as matrix materials. The weight ratios of E1, H1 and H2 are given below.

(35) ##STR00038## disclosed in WO 2011/073149

(36) Subsequently, the compound (1) is applied by vapor deposition with a thickness of 5 nm as an exciton and hole blocker.

(37) Next, as an electron transporter, a mixture of 50 wt. % (V2) and 50 wt. % Liq in a thickness of 25 nm, a 0.7 nm-thick KF layer and finally a 100 nm-thick Al electrode are applied by vapor deposition. All components are bonded to a glass cover in an inert nitrogen atmosphere.

(38) ##STR00039## disclosed in WO 2006/128800 A1

II.2 Production of an OLED Comprising Compound (2) as Host Material and Hole Blocker Material (OLED (2))

(39) As example II.1, except that the host material and the hole blocker material used is compound (2) according to synthesis example I.3 instead of compound (1).

II.3 Production of an OLED Comprising Compound (3) as Host Material and Hole Blocker Material (OLED (3))

(40) As example II.1, except that the host material and the hole blocker material used is compound (3) according to synthesis example 1.4 instead of compound (1).

II.4 Production of an OLED Comprising Comparative Compound (V7) as Host Material and Hole Blocker Material (OLED (V7))

(41) As example II.1, except that the host material and the hole blocker material used is compound (V7) according to synthesis example I.5 instead of compound (1).

(42) Results

(43) To characterize the OLEDs of examples II.1, II.2 and II.3 and the OLED of comparative example II.4, electroluminescence spectra are recorded at different currents and voltages. In addition, the current-voltage characteristic is measured in combination with the emitted light output. The light output can be converted to photometric parameters by calibration with a photometer. The data are shown in table 1.

II.5 Production of an OLEDs Comprising Compounds (4), (5) and (6) as Host Material and Hole Blocker Material (OLEDs (4), (5) and (6))

(44) As example II.1, except that the host material and the hole blocker material used is compound (4), (5) or (6), respectively according to synthesis example I.5 instead of compound (1).

(45) The OLEDs (4), (5) and (6) obtained emit blue light.

(46) TABLE-US-00001 TABLE 1 OLED Example CIE-x.sup.1) CIE-y.sup.2) Voltage 300 nits EQE.sup.4) 300 nits LD.sup.5) 300 nits (host and hole blocker) absolute values absolute values normalized values.sup.3) normalized values.sup.3) normalized values.sup.3) OLED II.1 (1) 0.177 0.347 0.798 7.683 3.635 OLED II.2 (2) 0.188 0.37 0.691 9.025 34.594 OLED II.3 (3) 0.188 0.381 0.716 7.935 4.421 OLED II.4 (V7) 0.18 0.329 1.000 1.000 1.000 .sup.1)CIE (International Commission on Illumination) color coordinate: x-coordinate .sup.2)CIE (International Commission on Illumination) color coordinate: y-coordinate .sup.3)Normalized values: Normalized relative to the values of comparative OLED II.4 (host and hole blocker material: (V7)) - the values of the comparative OLED II.4 (host and hole blocker material: (V7)) are set to 1.000 .sup.4)EQE: external quantum efficiency .sup.5)LD: lifetime

CONCLUSION

(47) The performance of the inventive OLEDs (1) to (3) is clearly superior compared with the performance of the comparative OLED (V7). The only difference between the inventive OLEDs and the comparative OLED is the material employed as host in the light emitting layer and as exciton and hole blocker, which is according to the present invention a phenoxasiline compound and according to the comparative example a phenazasiline compound. The superiority of the inventive phenoxasilines over phenazasilines is especially evident in the following OLED properties: i) Voltage: the OLEDs of the present invention comprising the phenoxasilines according to the present invention perform at significantly lower voltage than OLEDs comprising phenazasilines; ii) External quantum efficiency (EQE): the OLEDs of the present invention comprising the phenoxasilines according to the present invention show a significantly higher EQE than OLEDs comprising phenazasilines; iii) Lifetime (LD): the OLEDs of the present invention comprising the phenoxasilines according to the present invention show a significantly longer lifetime than OLEDs comprising phenazasilines; this is especially clear from the direct comparison of OLED II.2 (host and hole blocker material: (2)) and OLED II.4 (host and holeblocker material (V7)), wherein the substituents of the phenoxasiline (according to the present invention; (2)) and the phenazasiline (comparative example; (V7)) are identical.