Binuclear metal complexes and electronic devices, in particular organic electroluminescent devices containing said metal complexes

Abstract

The present invention relates to binuclear metal complexes and electronic devices, in particular organic electroluminescent devices containing said metal complexes. ##STR00001##

Claims

1. A compound of formula (1): ##STR00801## wherein M is the same or different in each instance and is iridium or rhodium; D is the same or different in each instance and is C or N, with the proviso that one C and one N are coordinated to each of the two M; X is the same or different in each instance and is CR or N; V is the same or different in each instance and is a group of formula (2) or (3): ##STR00802## wherein one of the dotted bonds denotes the bond to the corresponding 6-membered aryl or heteroaryl group in formula (1) and the two other dotted bonds each denote the bonds to the sub-ligands L; L is the same or different in each instance and is a bidentate monoanionic sub-ligand; X.sup.1 is the same or different in each instance and is CR or N; A.sup.1 is the same or different in each instance and is C(R).sub.2 or O; A.sup.2 is the same or different in each instance and is CR, P(═O), B, or SiR, with the proviso that, when A.sup.2=P(═O), B, or SiR, A.sup.1 is O and the A bonded to the A.sup.2 is not —C(═O)—NR′— or —C(═O)—O—; A is the same or different in each instance and is —CR═CR—, —C(═O)—NR′—, —C(═O)—O—, —CR.sub.2—CR.sub.2—, —CR.sub.2—O—, or a group of formula (4): ##STR00803## wherein the dotted bond denotes the position of the bond of a bidentate sub-ligand L or the corresponding 6-membered aryl or heteroaryl group in formula (1) to this structure and * denotes the position of the linkage of the unit of formula (4) to the central cyclic group; X.sup.2 is the same or different in each instance and is CR or N or two adjacent X.sup.2 groups together are NR, O, or S, so as to define a five-membered ring, and the remaining X.sup.2 are the same or different in each instance and are CR or N; or two adjacent X.sup.2 groups together are CR or N when one of the X.sup.3 groups in the cycle is N, so as to define a five-membered ring; with the proviso that not more than two adjacent X.sup.2 groups are N; X.sup.3 is C in each instance or one X.sup.3 group is N and the other X.sup.3 groups in the same cycle are C; with the proviso that two adjacent X.sup.2 groups together are CR or N when one of the X.sup.3 groups in the cycle is N; R is the same or different in each instance and is H, D, F, Cl, Br, I, N(R.sup.1).sub.2, CN, NO.sub.2, OR.sup.1, SR.sup.1, COOH, C(═O)N(R.sup.1).sub.2, Si(R.sup.1).sub.3, B(OR.sup.1).sub.2, C(═O)R.sup.1, P(═O)(R.sup.1).sub.2, S(═O)R.sup.1, S(═O).sub.2R.sup.1, OSO.sub.2R.sup.1, COO(cation), SO.sub.3(cation), OSO.sub.3(cation), OPO.sub.3(cation).sub.2, O(cation), N(R.sup.1).sub.3(anion), P(R.sup.1).sub.3(anion), a straight-chain alkyl group having 1 to 20 carbon atoms or an alkenyl or alkynyl group having 2 to 20 carbon atoms or a branched or cyclic alkyl group having 3 to 20 carbon atoms, wherein the alkyl, alkenyl, or alkynyl group in each case is optionally substituted by one or more R.sup.1 radicals, wherein one or more nonadjacent CH.sub.2 groups are optionally replaced by Si(R.sup.1).sub.2, C═O, NR.sup.1, O, S, or CONR.sup.1, or an aromatic or heteroaromatic ring system which has 5 to 40 aromatic ring atoms and is optionally substituted in each case by one or more R.sup.1 radicals; and wherein two R radicals together optionally define a ring system; R′ is the same or different in each instance and is H, D, a straight-chain alkyl group having 1 to 20 carbon atoms or a branched or cyclic alkyl group having 3 to 20 carbon atoms, wherein the alkyl group in each case is optionally substituted by one or more R.sup.1 radicals and wherein one or more nonadjacent CH.sub.2 groups are optionally replaced by Si(R.sup.1).sub.2, or an aromatic or heteroaromatic ring system which has 5 to 40 aromatic ring atoms and is optionally substituted in each case by one or more R.sup.1 radicals; R.sup.1 is the same or different in each instance and is H, D, F, Cl, Br, I, N(R.sup.2).sub.2, CN, NO.sub.2, OR.sup.2, SR.sup.2, Si(R.sup.2).sub.3, B(OR.sup.2).sub.2, C(═O)R.sup.2, P(═O)(R.sup.2).sub.2, S(═O)R.sup.2, S(═O).sub.2R.sup.2, OSO.sub.2R.sup.2, COO(cation), SO.sub.3(cation), OSO.sub.3(cation), OPO.sub.3(cation).sub.2, O(cation), N(R.sup.2).sub.3(anion), P(R.sup.2).sub.3(anion), a straight-chain alkyl group having 1 to 20 carbon atoms or an alkenyl or alkynyl group having 2 to 20 carbon atoms or a branched or cyclic alkyl group having 3 to 20 carbon atoms, wherein the alkyl, alkenyl, or alkynyl group in each case is optionally substituted by one or more R.sup.2 radicals, wherein one or more nonadjacent CH.sub.2 groups are optionally replaced by Si(R.sup.2).sub.2, C═O, NR.sup.2, O, S, or CONR.sup.2, or an aromatic or heteroaromatic ring system which has 5 to 40 aromatic ring atoms and is optionally substituted in each case by one or more R.sup.2 radicals; wherein two or more R.sup.1 radicals together optionally define a ring system; R.sup.2 is the same or different in each instance and is H, D, F, or an aliphatic, aromatic, or heteroaromatic organic radical having 1 to 20 carbon atoms, wherein one or more hydrogen atoms is also optionally replaced by F; cation is the same or different in each instance and is selected from the group consisting of proton, deuteron, alkali metal ions, alkaline earth metal ions, ammonium, tetraalkylammonium, and tetraalkylphosphonium; and anion is the same or different in each instance and is selected from the group consisting of halides, carboxylates R.sup.2—COO.sup.−, cyanide, cyanate, isocyanate, thiocyanate, thioisocyanate, hydroxide, BF.sub.4.sup.−, PF.sub.6.sup.−, B(C.sub.6F.sub.5).sub.4.sup.−, carbonate, and sulfonates.

2. The compound of claim 1, wherein both metals M are Ir(III) and the compound is uncharged.

3. The compound of claim 1, wherein the compound is selected from the group consisting of structures of formulae (1a′) and (1b′): ##STR00804## wherein the radicals R explicitly shown are each the same or different in each instance and are selected from the group consisting of H, D, F, CH.sub.3, and CD.sub.3.

4. The compound of claim 1, wherein the group of the formula (2) is the same or different in each instance and is selected from the group consisting of structures the formulae (5) through (8) and the group of formula (3) is the same or different in each instance and is selected from the group consisting of structures of formulae (9) through (13): ##STR00805## ##STR00806##

5. The compound of claim 1, wherein the group of formula (2) is the same or different in each instance and is selected from the group consisting of structures of formula (5′) and wherein the group of formula (3) is the same or different in each instance and is selected from the group consisting of structures of formulae (9′) or (9″): ##STR00807##

6. The compound of claim 1, wherein A is the same or different in each instance and is selected from the group consisting of —C(═O)—O—, —C(═O)—NR′—, and a group of formula (4), wherein the group of formula (4) is selected from the group consisting of structures of formulae (14) through (38): ##STR00808## ##STR00809## ##STR00810##

7. The compound of claim 1, wherein the group of formula (2) is the same or different in each instance and is selected from the group consisting of structures of formulae (2a) through (2m) and wherein the group of formula (3) is the same or different in each instance and is selected from the group consisting of structures of formulae (3a) through (3m): ##STR00811## ##STR00812## ##STR00813## ##STR00814## ##STR00815## ##STR00816##

8. The compound of claim 1, wherein V is the same or different in each instance and is selected from the group consisting of structures of formulae (5a″) and (5a′″): ##STR00817##

9. The compound of claim 1, wherein the bidentate sub-ligands L are the same or different in each instance and are selected from the group consisting of structures of formulae (L-1), (L-2), and (L-3): ##STR00818## wherein the dotted bond denotes the bond of the sub-ligand L to the group of formula (2) or (3); CyC is the same or different in each instance and is a substituted or unsubstituted aryl or heteroaryl group which has 5 to 14 aromatic ring atoms and coordinates to M via a carbon atom and is bonded to CyD via a covalent bond; CyD is the same or different in each instance and is a substituted or unsubstituted heteroaryl group which has 5 to 14 aromatic ring atoms and coordinates to M via a nitrogen atom or via a carbene carbon atom and is bonded to CyC via a covalent bond; and wherein two or more of the substituents together optionally define a ring system.

10. A process for preparing the compound of claim 1 comprising reacting the ligand with metal alkoxides of formula (57), with metal ketoketonates of formula (58), with metal halides of formula (59), with metal carboxylates of formula (60), or with iridium or rhodium compounds bearing both alkoxide and/or halide and/or hydroxyl and also ketoketonate radicals: ##STR00819## wherein Hal is F, Cl, Br, or I; and the iridium or rhodium reactants are optionally in the form of hydrates.

11. A formulation comprising at least one compound of claim 1 and at least one solvent.

12. An electronic device comprising at least one compound of claim 1.

13. The electronic device of claim 12, wherein the electronic device is an organic electroluminescent device and wherein the compound of formula (1) is present in the electroluminescent device as an emitting compound in one or more emitting layers.

Description

EXAMPLES

(1) The syntheses which follow, unless stated otherwise, are conducted under a protective gas atmosphere in dried solvents. The metal complexes are additionally handled with exclusion of light or under yellow light. The solvents and reagents can be purchased, for example, from Sigma-ALDRICH or ABCR. The respective figures in square brackets or the numbers quoted for individual compounds relate to the CAS numbers of the compounds known from the literature.

A: Synthesis of the Synthons

Example B1

(2) ##STR00397##

(3) A mixture of 31.4 g (100 mmol) of 5,5′-dibromo-2,2′-bipyridine [15862-18-7], 54.6 g (215 mmol) of bis(pinacolato)diborane [73183-34-3], 58.9 g (600 mmol) of potassium acetate, 2.3 g (8 mmol) of SPhos [657408-07-6], 1.3 mg (6 mmol) of palladium(II) acetate and 900 ml of 1,4-dioxane is heated under reflux for 16 h. The dioxane is removed on a rotary evaporator, and the black residue is worked up by extraction with 1000 ml of ethyl acetate and 500 ml of water in a separating funnel. The organic phase is washed once with 300 ml of water and once with 150 ml of saturated sodium chloride solution and filtered through a silica gel bed. The silica gel is washed with 2×250 ml of ethyl acetate. The filtrate is dried over sodium sulfate and concentrated. The residue is mixed with 400 ml of n-heptane and the suspension is heated to reflux for 1 h. After cooling, the solids are filtered off and washed twice with 30 ml each time of n-heptane. Yield: 33.1 g (81 mmol), 81%. Purity: about 98% by .sup.1H NMR.

Example B2

(4) ##STR00398##

(5) Compound B2 can be prepared analogously to the procedure from B1, using 5-bromo-2-(4-bromophenyl)pyrimidine [1263061-48-8] rather than 5,5′-dibromo-2,2′-bipyridine.

Example B3

(6) ##STR00399##

(7) A mixture of 40.8 g (100 mmol) of B1, 56.6 g (200 mmol) of 1-bromo-2-iodobenzene [583-55-1], 63.6 g (600 mmol) of sodium carbonate, 5.8 g (5 mmol) of tetrakis(triphenylphosphine)palladium(0) [14221-01-3], 1000 ml of 1,2-dimethoxyethane and 500 ml of water is heated under reflux for 60 h. After cooling, the precipitated solids are filtered off with suction and washed three times with 100 ml of ethanol. The crude product is dissolved in 1000 ml of dichloromethane (DCM) and filtered through a silica gel bed in the form of a DCM slurry. The silica gel is washed through three times with 100 ml each time of ethyl acetate. The dichloromethane is removed on a rotary evaporator down to 500 mbar at bath temperature 50° C. The solids that have precipitated out of the remaining ethyl acetate are filtered off and washed twice with 20 ml of ethyl acetate. The solids obtained are recrystallized once again from ethyl acetate at boiling. Yield 25.6 g (55 mmol), 55%, 95% by .sup.1H NMR.

Example B4

(8) ##STR00400##

(9) Compound B4 can be prepared analogously to the procedure of B3, except using unit B2 rather than B1. Yield: 52%.

Example B5

(10) ##STR00401##

(11) Compound B5 can be prepared analogously to the procedure of B3, except using 1-bromo-2-chlorobenzene [694-80-4] rather than 1-bromo-2-iodobenzene. Purification is effected by chromatography on a Torrent automated flash column system from Axel-Semrau. Yield: 67%.

Example B6

(12) ##STR00402##

(13) Compound B6 can be prepare analogously to the procedure of B4, except using 1-bromo-2-chlorobenzene rather than 1-bromo-2-iodobenzene. Purification is effected by chromatography on a Torrent automated flash column system from Axel-Semrau. Yield: 70%

Example B8

(14) ##STR00403##

(15) A mixture of 18.1 g (100 mmol) of 6-chlorotetralone [26673-31-4], 16.5 g (300 mmol) of propargylamine [2450-71-7], 796 mg [2 mmol] of sodium tetrachloroaurate(III) dihydrate and 200 ml of ethanol is stirred in an autoclave at 120° C. for 24 h. After cooling, the ethanol is removed under reduced pressure, the residue is taken up in 200 ml of ethyl acetate, the solution is washed three times with 200 ml of water and once with 100 ml of saturated sodium chloride solution and dried over magnesium sulfate, and then the latter is filtered off using a silica gel bed in the form of a slurry. After the ethyl acetate has been removed under reduced pressure, the residue is chromatographed on silica gel with n-heptane/ethyl acetate (1:2 v/v). Yield: 9.7 g (45 mmol), 45%. Purity: about 98% by .sup.1H NMR.

Example B9

(16) ##STR00404##

(17) A mixture of 25.1 g (100 mmol) of 2,5-dibromo-4-methylpyridine [3430-26-0], 15.6 g (100 mmol) of 4-chlorophenylboronic acid [1679-18-1], 27.6 g (200 mmol) of potassium carbonate, 1.57 g (6 mmol) of triphenylphosphine [603-35-0], 676 mg (3 mmol) of palladium(II) acetate [3375-31-3], 200 g of glass beads (diameter 3 mm), 200 ml of acetonitrile and 100 ml of ethanol is heated under reflux for 48 h. After cooling, the solvents are removed under reduced pressure, 500 ml of toluene are added, the mixture is washed twice with 300 ml each time of water and once with 200 ml of saturated sodium chloride solution, dried over magnesium sulfate and filtered through a silica gel bed in the form of a slurry, which is washed with 300 ml of toluene. After the toluene has been removed under reduced pressure, it is recrystallized once from methanol/ethanol (1:1 v/v) and once from n-heptane. Yield: 17.3 g (61 mmol), 61%. Purity: about 95% by .sup.1H NMR.

Example B10

(18) ##STR00405##

(19) B10 can be prepared analogously to the procedure described for example B9. For this purpose, 4-bromo-6-tert-butylpyrimidine [19136-36-8] is used rather than 2,5-dibromo-4-methylpyridine. Yield: 70%.

Example B11

(20) ##STR00406##

(21) A mixture of 28.3 g (100 mmol) of B9, 12.8 g (105 mmol) of phenylboronic acid, 31.8 g (300 mmol) of sodium carbonate, 787 mg (3 mmol) of triphenylphosphine, 225 mg (1 mmol) of palladium(II) acetate, 300 ml of toluene, 150 ml of ethanol and 300 ml of water is heated under reflux for 48 h. After cooling, the mixture is extended with 300 ml of toluene, and the organic phase is removed, washed once with 300 ml of water and once with 200 ml of saturated sodium chloride solution, and dried over magnesium sulfate. After the solvent has been removed, the residue is chromatographed on silica gel (toluene/ethyl acetate, 9:1 v/v). Yield: 17.1 g (61 mmol), 61%. Purity: about 97% by .sup.1H NMR.

(22) In an analogous manner, it is possible to synthesize the following compounds:

(23) TABLE-US-00004 Ex. Boronic ester Product Yield B12 07 08 56% B13 09 0 61% B14 55%

Example B15

(24) ##STR00413##

(25) A mixture of 164.2 g (500 mmol) of 2-(1,1,2,2,3,3-hexamethylindan-5-yl)-4,4,5,5-tetramethyl-[1,3,2]dioxaborolane [152418-16-9] (boronic acids can be used analogously), 142.0 g (500 mmol) of 5-bromo-2-iodopyridine [223463-13-6], 159.0 g (1.5 mol) of sodium carbonate, 5.8 g (5 mmol) of tetrakis(triphenylphosphino)palladium(0), 700 ml of toluene, 300 ml of ethanol and 700 ml of water is heated under reflux with good stirring for 16 h. After cooling, 1000 ml of toluene are added, the organic phase is removed and the aqueous phase is re-extracted with 300 ml of toluene. The combined organic phases are washed once with 500 ml of saturated sodium chloride solution. After the organic phase has been dried over sodium sulfate and the solvent has been removed under reduced pressure, the crude product is recrystallized twice from about 300 ml of EtOH. Yield: 130.8 g (365 mmol), 73%. Purity: about 95% by .sup.1H NMR.

(26) It is analogously possible to prepare the compounds which follow. The pyridine derivative used here is generally 5-bromo-2-iodopyridine ([223463-13-6]), which is not listed separately in the table which follows; only different pyridine derivatives are listed explicitly in the table. Recrystallization can be accomplished using solvents such as ethyl acetate, cyclohexane, toluene, acetonitrile, n-heptane, ethanol or methanol. It is also possible to use these solvents for hot extraction, or to purify by chromatography on silica gel in an automated column system (Torrent from Axel Semrau).

(27) TABLE-US-00005 Boronic acid/ester Ex. Pyridine Product Yield B16 69% B17 71% B18 78% B19 0 78% B20 81% B21 73% B22 68% B23 63%

Example B24

(28) Variant A:

(29) ##STR00430##

(30) A mixture of 35.8 g (100 mmol) of B15, 25.4 g (100 mmol) of bis(pinacolato)diborane [73183-34-3], 49.1 g (500 mmol) of potassium acetate, 1.5 g (2 mmol) of 1,1-bis(diphenylphosphino)ferrocenedichloropalladium(II) complex with DCM [95464-05-4], 200 g of glass beads (diameter 3 mm), 700 ml of 1,4-dioxane and 700 ml of toluene is heated under reflux for 16 h. After cooling, the suspension is filtered through a Celite bed and the solvent is removed under reduced pressure. The black residue is digested with 1000 ml of hot n-heptane, cyclohexane or toluene and filtered through a Celite bed while still hot, then concentrated to about 200 ml, in the course of which the product begins to crystallize. Alternatively, hot extraction with ethyl acetate is possible. The crystallization is completed in a refrigerator overnight, and the crystals are filtered off and washed with a little n-heptane. A second product fraction can be obtained from the mother liquor. Yield: 31.6 g (78 mmol), 78%. Purity: about 95% by .sup.1H NMR.

(31) Variant B: Conversion of Aryl Chlorides

(32) As variant A, except that, rather than 1,1-bis(diphenylphosphino)-ferrocenedichloropalladium(II) complex with DCM, 2 mmol of SPhos [657408-07-6] and 1 mmol of palladium(II) acetate are used.

(33) In an analogous manner, it is possible to prepare the following compounds, and it is also possible to use cyclohexane, toluene, acetonitrile or mixtures of said solvents for purification rather than n-heptane:

(34) TABLE-US-00006 Bromide- Variant A Ex. Chloride- Variant B Product Yield B25 85% B26 80% B27 83% B28 77% B29 0 67% B30 70% B31 80% B32 80% B33 78% B34 0 74% B35 70% B36 68% B37 76% B38 83% B39 0 85% B40 55% B41 72% B42 78% B43 82% B44 0 60% B45 75% B46 88% B47 78% B48 82% B49 0 80% B50 85% B51 88% B52 76% B53 81% B54 0 78% B55 75% B163 51%

Example B56

(35) ##STR00495##

(36) A mixture of 28.1 g (100 mmol) of B25, 28.2 g (100 mmol) of 1-bromo-2-iodobenzene [583-55-1], 31.8 g (300 mmol) of sodium carbonate, 787 mg (3 mmol) of triphenylphosphine, 225 mg (1 mmol) of palladium(II) acetate, 300 ml of toluene, 150 ml of ethanol and 300 ml of water is heated under reflux for 24 h. After cooling, the mixture is extended with 500 ml of toluene, and the organic phase is removed, washed once with 500 ml of water and once with 500 ml of saturated sodium chloride solution and dried over magnesium sulfate. After the solvent has been removed, the residue is recrystallized from ethyl acetate/n-heptane or chromatographed on silica gel (toluene/ethyl acetate, 9:1 v/v). Yield: 22.7 g (73 mmol), 73%. Purity: about 97% by .sup.1H NMR.

(37) The compounds which follow can be prepared in an analogous manner, and recrystallization can be accomplished using solvents such as ethyl acetate, cyclohexane, toluene, acetonitrile, n-heptane, ethanol or methanol, for example. It is also possible to use these solvents for hot extraction, or to purify by chromatography on silica gel in an automated column system (Torrent from Axel Semrau).

(38) TABLE-US-00007 Ex. Boronic ester Product Yield B57 56% B58 72% B59 00 01 71% B60 02 03 70% B61 04 05 69% B62 06 07 67% B63 08 09 63% B64 0 70% B65 73% B66 72% B67 48% B68 65% B69 0 65% B70 68% B71 77% B72 70% B73 66% B74 0 71% B75 64% B76 58% B77 62% B78 75% B79 0 78% B80 82% B164 63% The aqueous phase is extracted three times with 200 ml each time of DCM; the combined organic phases are processed further.

Example B81

(39) ##STR00546##

(40) A mixture of 36.4 g (100 mmol) of 2,2′-(5-chloro-1,3-phenylene)bis[4,4,5,5-tetramethyl-1,3,2-dioxaborolane] [1417036-49-7], 65.2 g (210 mmol) of B56, 42.4 g (400 mmol) of sodium carbonate, 1.57 g (6 mmol) of triphenylphosphine, 500 mg (2 mmol) of palladium(II) acetate, 500 ml of toluene, 200 ml of ethanol and 500 ml of water is heated under reflux for 48 h. After cooling, the mixture is extended with 500 ml of toluene, and the organic phase is removed, washed once with 500 ml of water and once with 500 ml of saturated sodium chloride solution and dried over magnesium sulfate. After the solvent has been removed, the residue is chromatographed on silica gel (n-heptane/ethyl acetate, 2:1 v/v). Yield: 41.4 g (68 mmol), 68%. Purity: about 95% by .sup.1H NMR.

(41) The compounds which follow can be prepared in an analogous manner, and recrystallization can be accomplished using solvents such as ethyl acetate, cyclohexane, toluene, acetonitrile, n-heptane, ethanol or methanol, for example. It is also possible to use these solvents for hot extraction, or to purify by chromatography on silica gel in an automated column system (Torrent from Axel Semrau).

(42) TABLE-US-00008 Ex. Bromide Product Yield B82 67% B83 0 62% B84 55% B85 63% B86 60% B87 61% B88 0 58% B89 56% B90 60% B91 64% B92 60% B165 0 44% The aqueous phase is extracted three times with 200 ml each time of DCM; the combined organic phases are processed further.

Example B93

(43) ##STR00571##

(44) A mixture of 17.1 g (100 mmol) of 4-(2-pyridyl)phenol [51035-40-6] and 12.9 g (100 mmol) of diisopropylethylamine [7087-68-5] is stirred in 400 ml of dichloromethane at room temperature for 10 min. 6.2 ml (40 mmol) of 5-chloroisophthaloyl chloride [2855-02-9], dissolved in 30 ml of dichloromethane, are added dropwise, and the reaction mixture is stirred at room temperature for 14 h. Subsequently, 10 ml of water are added dropwise and the reaction mixture is transferred into a separating funnel. The organic phase is washed twice with 100 ml of water and once with 50 ml of saturated NaCl solution, dried over sodium sulfate and concentrated to dryness. Yield: 18.0 g (38 mmol), 95%. Purity: about 95% by .sup.1H NMR.

(45) The following compounds can be prepared in an analogous manner; the molar amounts of the reactants used are specified if they differ from those described in the procedure for B93.

(46) TABLE-US-00009 Alcohol or amine Acid chloride Ex. Reaction time Product Yield B94 90% 12 h   B95 96% 1 h   B96 0 88% 0.5 h B97 76% 100 mmol 50 mmol 14 h, reflux B98 80% 100 mmol 50 mmol 10 h   B99 73% 100 mmol 50 mmol 18 h, reflux B100 0 78% 100 mmol 50 mmol 5 h  

Example B101

(47) ##STR00593##

(48) 2.0 g (50 mmol) of sodium hydride (60% dispersion in paraffin oil) [7646-69-7] are suspended in 300 ml of THF, then 5.0 g (10 mmol) of B95 are added, and the suspension is stirred at room temperature for 30 minutes. Subsequently, 1.2 ml of iodomethane (50 mmol) [74-88-4] are added, and the reaction mixture is stirred at room temperature for 50 h. 20 ml of conc. ammonia solution are added, the mixture is stirred for a further 30 minutes, and the solvent is largely drawn off under reduced pressure. The residue is taken up in 300 ml of dichloromethane, washed once with 200 ml of 5% by weight aqueous ammonia, twice with 100 ml each time of water and once with 100 ml of saturated sodium chloride solution, and then dried over magnesium sulfate. The dichloromethane is removed under reduced pressure and the crude product is recrystallized from ethyl acetate/methanol. Yield: 4.3 g (8 mmol), 80%. Purity: about 98% by .sup.1H NMR.

(49) In an analogous manner, it is possible to prepare the following compounds:

(50) TABLE-US-00010 Ex. Reactant Product Yield B102 70% B103 69% B104 72%

Example B105

(51) ##STR00600##

(52) A mixture of 36.4 g (100 mmol) of 2,2′-(5-chloro-1,3-phenylene)bis[4,4,5,5-tetramethyl-1,3,2-dioxaborolane] [1417036-49-7], 70.6 g (210 mmol) of B69, 42.4 g (400 mmol) of sodium carbonate, 2.3 g (2 mmol) of tetrakis(triphenylphosphine)palladium(0), 1000 ml of 1,2-dimethoxyethane and 500 ml of water is heated under reflux for 48 h. After cooling, the precipitated solids are filtered off with suction and washed twice with 20 ml of ethanol. The solids are dissolved in 500 ml of dichloromethane and filtered through a Celite bed. The filtrate is concentrated down to 100 ml, then 400 ml of ethanol are added and the precipitated solids are filtered off with suction. The crude product is recrystallized once from ethyl acetate. Yield: 43.6 g (70 mmol), 70%. Purity: about 96% by .sup.1H NMR.

(53) The compounds which follow can be prepared in an analogous manner, and recrystallization can be accomplished using solvents such as ethyl acetate, cyclohexane, toluene, acetonitrile, n-heptane, ethanol or methanol, for example. It is also possible to use these solvents for hot extraction, or to purify by chromatography on silica gel in an automated column system (Torrent from Axel Semrau).

(54) TABLE-US-00011 B106 01 02 64% B107 03 04 54% B108 05 06 75% B109 07 08 71% B110 09 0 58% B111 60% B112 66% B113 70% B114 70% B115 0 63% B116 60% B117 61%

Example B119

(55) ##STR00625##

(56) A mixture of 57.1 g (100 mmol) of B81, 25.4 g (100 mmol) of bis(pinacolato)diborane [73183-34-3], 49.1 g (500 mmol) of potassium acetate, 2 mmol of SPhos [657408-07-6], 1 mmol of palladium(II) acetate, 200 g of glass beads (diameter 3 mm) and 700 ml of 1,4-dioxane is heated to reflux for 16 h while stirring. After cooling, the suspension is filtered through a Celite bed and the solvent is removed under reduced pressure. The black residue is digested with 1000 ml of hot ethyl acetate and filtered through a Celite bed while still hot and then concentrated to about 200 ml, in the course of which the product begins to crystallize. The crystallization is completed in a refrigerator overnight, and the crystals are filtered off and washed with a little ethyl acetate. A second product fraction can be obtained from the mother liquor. Yield: 31.6 g (78 mmol), 78%. Purity: about 95% by .sup.1H NMR.

(57) The following compounds can be prepared in an analogous manner, and it is also possible to use toluene, n-heptane, cyclohexane, dichloromethane or acetonitrile rather than ethyl acetate for recrystallization or for hot extraction in the case of sparingly soluble:

(58) TABLE-US-00012 Ex. Bromide Product Yield B120 80% B121 84% B122 0 71% B123 80% B124 85% B125 82% B126 77% B127 0 72% B128 77% B129 80% B130 81% B131 88% B132 0 79% B133 76% B134 89% B135 84% B136 79% B137 0 75% B138 77% B139 80% B140 82% B141 88% B142 0 90% B143 76% B144 80% B145 81% B146 84% B147 0 74% B148 73% B149 76% B150 72% B151 75% B166 0 67%

Example B152

(59) ##STR00692##

(60) Preparation according to G. Markopoulos et al., Angew. Chem, Int. Ed., 2012, 51, 12884.

(61) ##STR00693##

(62) Procedure according to JP 2000-169400. To a solution of 36.6 g (100 mmol) of 1,3-bis(2-bromophenyl)-2-propen-1-one [126824-93-9], stage a), in 300 ml of dry acetone are added 5.7 g [105 mmol] of sodium methoxide in portions, and then the mixture is stirred at 40° C. for 12 h. The solvent is removed under reduced pressure, and the residue is taken up in ethyl acetate, washed three times with 200 ml each time of water and twice with 200 ml each time of saturated sodium chloride solution, and dried over magnesium sulfate. The oil obtained after removal of the solvent under reduced pressure is subjected to flash chromatography (Torrent CombiFlash, from Axel Semrau). Yield: 17.9 g (44 mmol), 44%. Purity: about 97% by .sup.1H NMR.

(63) ##STR00694##

(64) To a solution of 2-chlorophenylmagnesium bromide (200 mmol) [36692-27-0] in 200 ml of di-n-butyl ether are added, at 0° C., 2.4 g (2.4 mmol) of anhydrous copper(I) chloride [7758-89-6], and the mixture is stirred for a further 30 min. Then a solution of 40.6 g (100 mmol) of stage b) in 200 ml of toluene is added dropwise over the course of 30 min. and the mixture is stirred at 0° C. for a further 5 h. The reaction mixture is quenched by cautiously adding 100 ml of water and then 220 ml of 1 N hydrochloric acid. The organic phase is separated off and washed twice with 200 ml each time of water, once with 200 ml of saturated sodium hydrogen carbonate solution and once with 200 ml of saturated sodium chloride solution, and dried over magnesium sulfate. The oil obtained after removal of the solvent under reduced pressure is filtered with toluene through silica gel. The crude product thus obtained is converted further without further purification. Yield: 49.8 g (96 mmol), 96%. Purity: about 90-95% by .sup.1H NMR.

(65) ##STR00695##

(66) To a solution, cooled to 0° C., of 51.9 g (100 mmol) of stage c) in 500 ml of dichloromethane (DCM) are added 1.0 ml of trifluoromethanesulfonic acid and then, in portions, 50 g of phosphorus pentoxide. The mixture is allowed to warm up to room temperature and stirred for a further 2 h. The phosphorus pentoxide is decanted off and suspended in 200 ml of DCM, and decanted off again. The combined DCM phases are washed twice with water and once with saturated sodium chloride solution and dried over magnesium sulfate. The wax obtained after removal of the solvent under reduced pressure is subjected to flash chromatography (Torrent CombiFlash, from Axel Semrau). Yield: 31.5 g (63 mmol), 63%, isomer mixture. Purity: about 90-95% by .sup.1H NMR.

(67) ##STR00696##

(68) A mixture of 25.0 g (50 mmol) of stage d), 2 g of Pd/C (10%), 200 ml of methanol and 300 ml of ethyl acetate is contacted with hydrogen at 3 bar in a stirred autoclave, and hydrogenation is effected at 30° C. until hydrogen absorption has ended. The mixture is filtered through a Celite bed in the form of an ethyl acetate slurry and the filtrate is concentrated to dryness. The oil thus obtained is subjected to flash chromatography (Torrent CombiFlash, from Axel Semrau). Yield: 17.2 g (34 mmol), 68%. Purity: about 95% by .sup.1H NMR (cis,cis isomer).

(69) The following compounds can be prepared in an analogous manner:

(70) TABLE-US-00013 Reactants Yield Ex. if different than B106 Product a) to e) B153 21% B154 00 19% B155 01 02 14%

Example B156

(71) ##STR00703##

(72) A mixture of 54.5 g (100 mmol) of B152, 59.0 g (210 mmol) of 2-phenyl-5-(4,4,5,5-tetramethyl-[1,3,2]dioxaborolan-2-yl)pyridine [879291-27-7], 127.4 g (600 mmol) of tripotassium phosphate, 1.57 g (6 mmol) of triphenylphosphine and 449 mg (2 mmol) of palladium(II) acetate in 750 ml of toluene, 300 ml of dioxane and 500 ml of water is heated under reflux for 30 h. After cooling, the organic phase is separated off, washed twice with 300 ml each time of water and once with 300 ml of saturated sodium chloride solution, and dried over magnesium sulfate. The magnesium sulfate is filtered off using a Celite bed in the form of a toluene slurry, the filtrate is concentrated to dryness under reduced pressure and the remaining foam is recrystallized from acetonitrile/ethyl acetate. Yield: 41.8 g (64 mmol) 64%. Purity: about 95% by .sup.1H NMR.

(73) The following compounds can be prepared in an analogous manner:

(74) TABLE-US-00014 Ex. Reactants Product Yield B157 04 05 68% B158 B154 B46  06 60% B159 B154 B35  07 60% B160 B154 B53  08 69% B161 B155 B55  09 61% B162 B153 B124 0 65%

B. Synthesis of the Ligands

Example L1

(75) Variant A:

(76) ##STR00711##

(77) A mixture of 7.0 g (15 mmol) of B3, 19.9 g (30.0 mmol) of B120, 9.5 g (90 mmol) of sodium carbonate, 340 mg (1.3 mmol) of triphenylphosphine, 98 mg (0.44 mmol) of palladium(II) acetate, 200 ml of toluene, 100 ml of ethanol and 200 ml of water is heated under reflux for 40 h. After cooling, the precipitated solids are filtered off with suction and washed twice with 30 ml each time of ethanol. The crude product is dissolved in 300 ml of dichloromethane and filtered through a silica gel bed. The silica gel bed is washed through three times with 200 ml each time of dichloromethane/ethyl acetate 1:1. The filtrate is washed twice with water and once with saturated sodium chloride solution and dried over sodium sulfate. The filtrate is concentrated to dryness. The residue is chromatographed with an ethyl acetate/heptane eluent mixture on silica gel (automated flash column system from Axel Semrau). Yield: 10.7 g (7.8 mmol), 52%. Purity: about 98% by .sup.1H NMR.

(78) Variant B:

(79) A mixture of 5.7 g (15 mmol) of B5, 19.9 g (30.0 mmol) of B120, 13.8 g (60 mmol) of potassium phosphate monohydrate, 507 mg (0.6 mmol) of XPhos palladacycle Gen. 3 [1445085-55-1], 200 ml of THE and 100 ml of water is heated under reflux for 20 h. After cooling, the precipitated solids are filtered off with suction and washed twice with 30 ml each time of water and twice with 30 ml each time of ethanol. Purification is effected as described in variant A. Yield: 13.2 g (9.6 mmol), 64%. Purity: about 99% by .sup.1H NMR.

(80) The compounds which follow can be prepared analogously to the procedure described for L1 (variant A or B). In this case, it is also possible to use toluene, cyclohexane, ethyl acetate or dimethylformamide for purification by recrystallization or hot extraction. Alternatively, the ligands can be purified by chromatography.

(81) TABLE-US-00015 Reactants Ex. Variant Product Yield L2 B3 + B119 A 56% L3 B5 + B123 B 54% L4 B3 + B139 A 62% L5 B3 + B149 A 50% L6 B5 + B138 B 64% L7 B5 + B127 B 60% L8 B3 + B136 A 48% L9 B5 + B140 B 59% L10 B5 + B129 B 0 64% L11 B5 + B125 B 57% L12 B5 + B126 B 61% L13 B3 + B128 A 55% L14 B5 + B142 B 57% L15 B1 + B157 B 61% L16 B1 + B158 B 57% L17 B1 + B162 B 54% L18 B4 + B119 A 55% L19 B6 + B120 B 58% L20 B4 + B126 A 0 57% L21 B4 + B128 A 61% L22 B6 + B150 B 60% L23 B4 + B149 A 61% L24 B4 + B145 A 67% L25 B6 + B130 B 58% L26 B2 + B156 B 70% L27 B2 + B159 B 62% L28 B2 + B161 B 66% L29 B5 + B166 B 54%

C: Synthesis of the Metal Complexes

(82) Variant A: Complexes with C—N— or C—O— donor set of the I1-Ir.sub.2(L1) and I2-Ir.sub.2(L1) type

(83) ##STR00740##

(84) A mixture of 13.8 g (10 mmol) of ligand L1, 9.8 g (20 mmol) of trisacetylacetonatoiridium(III) [15635-87-7] and 100 g of hydroquinone [123-31-9] is initially charged in a 1000 ml two-neck round-bottom flask with a glass-sheathed magnetic bar. The flask is provided with a water separator (for media of lower density than water) and an air condenser with argon blanketing and placed into a metal heating bath. The apparatus is purged with argon from the top via the argon blanketing system for 15 min, allowing the argon to flow out of the side neck of the two-neck flask. Through the side neck of the two-neck flask, a glass-sheathed Pt-100 thermocouple is introduced into the flask and the end is positioned just above the magnetic stirrer bar. The apparatus is then thermally insulated with several loose windings of domestic aluminum foil, the insulation being run up to the middle of the riser tube of the water separator. Then the apparatus is heated rapidly with a heated laboratory stirrer system to 250° C., measured with the Pt-100 thermal sensor which dips into the molten stirred reaction mixture. Over the next 2 h, the reaction mixture is kept at 250° C., in the course of which a small amount of condensate is distilled off and collects in the water separator. The reaction mixture is left to cool down to 190° C., then 100 ml of ethylene glycol are added dropwise. The mixture is left to cool down further to 80° C. and then 500 ml of methanol are added dropwise; the mixture is heated at reflux for 1 h. The suspension thus obtained is filtered through a double-ended frit, and the solids are washed twice with 50 ml of methanol and then dried under reduced pressure. The solids thus obtained are dissolved in 200 ml of dichloromethane and filtered through about 1 kg of silica gel in the form of a dichloromethane slurry (column diameter about 18 cm) with exclusion of air in the dark, leaving dark-colored components at the start. The core fraction is cut out and concentrated on a rotary evaporator, with simultaneous continuous dropwise addition of MeOH until crystallization. After removal with suction, washing with a little MeOH and drying under reduced pressure, further purification of the diastereomer product mixture is effected.

(85) The diastereomeric metal complex mixture containing ΔΔ and ∧∧ isomers (racemic) and ∧Δ isomer (meso) and additionally small proportions of meridional isomers is dissolved in 300 ml of dichloromethane, applied to 100 g of silica gel and subjected to chromatographic separation using a silica gel column in the form of a toluene slurry (amount of silica gel about 1.7 kg). The eluent used is at first toluene, later toluene with small proportions of ethyl acetate. 5.1 g of the isomer that elutes earlier, called isomer 1 (I1) hereinafter, and 5.3 g of isomer that elutes later, called isomer 2 (I2) hereinafter, are obtained. Isomer 1 (I1) and isomer 2 (I2) are purified further separately by hot extraction four times with n-butyl acetate for isomer 1 and toluene for isomer 2 (amount initially charged about 150 ml in each case, extraction thimble: standard Soxhlett thimbles made of cellulose from Whatman) with careful exclusion of air and light. Finally, the products are subjected to heat treatment under high vacuum at 280° C. Yield: isomer 1 (I1) 3.7 g of red solid (2.1 mmol), 21% based on the amount of ligands used. Purity: >99.7% by HPLC; isomer 2 (I2) 3.7 g of red solid (2.1 mmol), 21% based on the amount of ligands used. Purity 99.8% by HPLC. The metal complexes are finally subjected to heat treatment under high vacuum (10.sup.−6 mbar) at 250° C.

(86) The reported yields for isomer 1 (I1) or isomer 2 (I2) are always based on the amount of ligand used.

(87) The images of complexes shown hereinafter always show just one isomer. The isomer mixture can be separated, but can be used equally well as an isomer mixture in the OLED device. The metal complexes shown hereinafter can in principle be purified by chromatography (typically use of an automated column system (Torrent from Axel Semrau), recrystallization or hot extraction. Residual solvents can be removed by heat treatment under high vacuum at typically 250-330° C. The compounds which follow can be synthesized analogously. The reaction conditions are specified by way of example for isomer 1 (I1). The chromatographic separation of the diastereomer mixture that is typically obtained is effected on flash silica gel in an automated column system (Torrent from Axel Semrau).

(88) Analogously, by sequential addition of first 10 mmol of Ir(acac).sub.3 and conducting the reaction at 250° C. for 1 h and then adding 10 mmol of Rh(acac).sub.3[14284-92-5] and conducting the reaction further at 250° C. for 1 h and subsequent workup and purification as specified above, mixed-metallic Rh—Ir complexes can be obtained.

(89) Variant B: Complexes with C—C— Donor Set, Carbene Complexes

(90) A suspension of 10 mmol of the carbene ligand and 40 mmol of Ag.sub.2O in 300 ml of dioxane is stirred at 30° C. for 12 h. Then 20 mmol of [Ir(COD)Cl].sub.2 [12112-67-3] are added and the mixture is heated under reflux for 12 h. The solids are filtered off while the mixture is still hot and they are washed three times with 50 ml each time of hot dioxane, and the filtrates are combined and concentrated to dryness under reduced pressure. The crude product thus obtained is chromatographed twice on basic alumina with ethyl acetate/cyclohexane or toluene. The product is purified further by continuous hot extraction five times with acetonitrile and hot extraction twice with ethyl acetate/acetonitrile (amount initially charged in each case about 200 ml, extraction thimble: standard Soxhlet thimbles made from cellulose from Whatman) with careful exclusion of air and light. Finally, the product is sublimed or heat-treated under high vacuum. Purity: >99.8% by HPLC.

(91) TABLE-US-00016 Product/reaction conditions/ Ex. Reactant hot extractant (HE) Yield Variante A I1-Rh.sub.2(L1) L1  Rh(acac).sub.3 [14284- 92-5] rather than Ir(acac).sub.3 17% I1-Rh.sub.2(L1) 250° C., 2 h HE: toluene I2-Rh.sub.2(L1) L1  I2-Rh.sub.2(L1) 15% Rh(acac).sub.3 HE: toluene [14284- 92-5] rather than Ir(acac).sub.3 I1-Rh- Ir(L1) L1  1.10 mmol Ir(acac).sub.3 [15635- 87-7] 2.10 mmol Rh(acac).sub.3 [14284- 92-5] 15% I1-Rh-Ir(L1) 250° C., 2 h HE: toluene I1-Ir.sub.2(L2) L2  20% I1-Ir.sub.2(L2) 250° C., 2 h HE: toluene I2-Ir.sub.2(L2) L2  I2-Ir.sub.2(L2) 23% HE: toluene I1-Ir.sub.2(L3) L3  24% I1-Ir.sub.2(L3) 250° C., 2 h HE: ethyl acetate I2-Ir.sub.2(L3) L3  I2-Ir.sub.2(L3) 22% HE: ethyl actate I1-Ir.sub.2(L4) L4  21% I1-Ir.sub.2(L4) 260° C., 3 h HE: n-butyl acetate I2-Ir.sub.2(L4) L4  I2-Ir.sub.2(L4) 24% HE: ethyl acetate I1-Ir.sub.2(L5) L5  18% I1-Ir.sub.2(L5) 250° C., 1 h HE: ethyl acetate I2-Ir.sub.2(L5) L5  I2-Ir.sub.2(L5) 17% HE: ethyl acetate I1-Ir.sub.2(L6) L6  24% I1-Ir.sub.2(L6) 260° C., 2 h HE: dichloromethane I2-Ir.sub.2(L6) L6  I2-Ir.sub.2(L6) 21% HE: o-xylene I1-Ir.sub.2(L7) L7  20% I1-Ir.sub.2(L7) 260° C., 2 h HE: dichloromethane I2-Ir.sub.2(L7) L7  I2-Ir.sub.2(L7) 22% HE: dichloromethane I1-Ir.sub.2(L8) L8  14% I1-Ir.sub.2(L8) 240° C., 1 h Recrystallization: dimethylformamide I2-Ir.sub.2(L8) L8  I2-Ir.sub.2(L8) 12% Recrystallization: dimethylactamide I1-Ir.sub.2(L9) L9  0 19% I1-Ir.sub.2(L9) 260° C., 3 h HE: toluene I2-Ir.sub.2(L9) L9  I2-Ir.sub.2(L9) 21% HE: n-butyl acetate I1-Ir.sub.2(L10) + I2-Ir.sub.2(L10) L10 42% I1-Ir.sub.2(L10) + I2-Ir.sub.2(L10) 240° C., 3 h HE: ethyl acetate Diastereomer mixture could not be separated, used as a mixture. Ir.sub.2(L11) L11 44% Ir.sub.2(L11) 250° C., 2 h HE: toluene A disastereomer pair is preferentially formed. Ir.sub.2(L12) L12 41% Ir.sub.2(L12) 250° C., 2 h HE: n-butyl acetate A disastereomer pair is preferentially formed. I1-Ir.sub.2(L13) L13 23% I1-Ir.sub.2(L13) 250° C., 2 h HE: ethyl acetate I2-Ir.sub.2(L13) L13 I2-Ir.sub.2(L13) 20% HE: ethyl acetate I1-Ir.sub.2(L14) L14 23% I1-Ir.sub.2(L14) 260° C., 3 h HE: o-xylene I2-Ir.sub.2(L14) L14 I2-Ir.sub.2(L14) 18% HE: toluene I1-Ir.sub.2(L15) L15 19% I1-Ir.sub.2(L15) 250° C., 1 h HE: ethyl acetate I2-Ir.sub.2(L15) L15 I2-Ir.sub.2(L15) 18% HE: ethyl acetate I1-Ir.sub.2(L16) L16 17% I1-Ir.sub.2(L16) 250° C., 1 h HE: ethyl acetate/acetonitrile 1:1 I2-Ir.sub.2(L16) L16 I2-Ir.sub.2(L16) 15% HE: ethyl acetate I1-Ir.sub.2(L17) + I2-Ir.sub.2(L17) L17 38% I1-Ir.sub.2(L17) + I2-Ir.sub.2(L17) 250° C., 1 h HE: ethyl acetate/acetonitrile 1:1 Diastereomer mixture could not be separated. I1-Ir.sub.2(L18) L18 30% I1-Ir.sub.2(L18) 250° C., 2 h HE: toluene I2-Ir.sub.2(L18) L18 I2-Ir.sub.2(L18) 32% HE: dichloromethane I1-Ir.sub.2(L19) L19 0 28% I1-Ir.sub.2(L19) 250° C., 2 h HE: o-xylene I2-Ir.sub.2(L19) L19 I2-Ir.sub.2(L19) 27% HE: toluene Ir.sub.2(L20) L20 54% I1-Ir.sub.2(L20) 250° C., 2 h HE: toluene A disastereomer pair is preferentially formed. I1-Ir.sub.2(L21) + I2-Ir.sub.2(L21) L21 62% I1-Ir.sub.2(L21) + I2-Ir.sub.2(L21) 250° C., 2 h HE: ethyl acetate Diastereomer mixture could not be separated. I1-Ir.sub.2(L22) L22 28% I1-Ir.sub.2(L22) 265° C., 3 h HE: n-butyl acetate I2-Ir.sub.2(L22) L22 I2-Ir.sub.2(L22) 26% HE: dichloromethane I1-Ir.sub.2(L23) L23 23% I1-Ir.sub.2(L23) 250° C., 1 h HE: ethyl acetate I2-Ir.sub.2(L23) L23 I2-Ir.sub.2(L23) 21% HE: ethyl acetate I1-Ir.sub.2(L24) L24 32% I1-Ir.sub.2(L24) 250° C., 2 h HE: o-xylene I2-Ir.sub.2Ir.sub.2(L24) L24 I2-Ir.sub.2(L24) 30% HE: dichloromethane I1-Ir.sub.2(L25) + I2-Ir.sub.2(L25) L25 57% I1-Ir.sub.2(L25) + I2-Ir.sub.2(L25) 250° C., 2 h HE: ethyl acetate Diastereomer mixture could not be separated. I1-Ir.sub.2(L26) L26 27% I1-Ir.sub.2(L26) 250° C., 2 h HE: n-butyl acetate I2-Ir.sub.2(L26) L26 I2-Ir.sub.2(L26) 27% HE: n-butyl acetate I1-Ir.sub.2(L27) + I2-Ir.sub.2(L27) L27 65% I1-Ir.sub.2(L27) + I2-Ir.sub.2(L27) 250° C., 2 h Diastereomer mixture could not be separated Ir.sub.2(L28) L28 26% Ir.sub.2(L28) 250° C., 2 h HE: ethyl acetate A diasteromer pair is preferentially formed. Variante B Ir.sub.2(L29) L29 0 23%

D: Functionalization of the Metal Complexes

(92) 1) Halogenation of the Iridium Complexes:

(93) To a solution or suspension of 10 mmol of a complex bearing A×C—H groups (with A=1-4) in the para position to the iridium in the bidentate sub-ligand in 500 ml to 2000 ml of dichloromethane according to the solubility of the metal complexes is added, in the dark and with exclusion of air, at −30 to +30° C., A×10.5 mmol of N-halosuccinimide (halogen: Cl, Br, I), and the mixture is stirred for 20 h. Complexes of sparing solubility in DCM may also be converted in other solvents (TCE, THF, DMF, chlorobenzene, etc.) and at elevated temperature. Subsequently, the solvent is substantially removed under reduced pressure. The residue is extracted by boiling with 100 ml of methanol, and the solids are filtered off with suction, washed three times with 30 ml of methanol and then dried under reduced pressure. This gives the iridium complexes brominated/halogenated in the para position to the iridium. Complexes having a HOMO (CV) of about −5.1 to −5.0 eV and of smaller magnitude have a tendency to oxidation (Ir(III).fwdarw.Ir(IV)), the oxidizing agent being bromine released from NBS. This oxidation reaction is apparent by a distinct green hue or brown hue in the otherwise yellow to red solution/suspension of the emitters. In such cases, 1-2 further equivalents of NBS are added. For workup, 300-500 ml of methanol and 4 ml of hydrazine hydrate as reducing agent are added, which causes the green or brown solution/suspension to turn yellow or red (reduction of Ir(IV).fwdarw.Ir(III)). Then the solvent is substantially drawn off under reduced pressure, 300 ml of methanol are added, and the solids are filtered off with suction, washed three times with 100 ml each time of methanol and dried under reduced pressure.

(94) Substoichiometric brominations, for example mono- and dibrominations, of complexes having 4 C—H groups in the para position to the iridium atoms usually proceed less selectively than the stoichiometric brominations. The crude products of these brominations can be separated by chromatography (CombiFlash Torrent from A. Semrau).

(95) Synthesis of Ir.sub.2(L1-4Br):

(96) ##STR00771##

(97) To a suspension of 17.6 g (10 mmol) of I1-Ir.sub.2(L1) in 2000 ml of DCM are added 5.0 g (45 mmol) of N-bromosuccinimide all at once and then the mixture is stirred at room temperature for 20 h. 2 ml of hydrazine hydrate and then 300 ml of MeOH are added. After removing about 1900 ml of the DCM under reduced pressure, the red solids are filtered off with suction, washed three times with about 50 ml of methanol and then dried under reduced pressure. Yield: 18.6 g (9.0 mmol), 90%; purity: >98.0% by NMR.

(98) The following compounds can be synthesized in an analogous manner:

(99) TABLE-US-00017 Ex. Reactant Product/amount of NBS Yield I2-Ir.sub.2(L1- I2-Ir.sub.2(L1) I2-Ir.sub.2(L1-4Br) 88% 4Br) 4.5 equiv. NBS I1-Rh.sub.2(L1- 4Br) I1- Rh.sub.2(L1) 70% I1-Rh.sub.2(L1-4Br) 4.5 equiv. NBS I2-Rh.sub.2(L1- I2- I2-Rh.sub.2(L1-4Br) 70% 4Br) Rh.sub.2(L1) 4.5 equiv. NBS I1-Ir.sub.2(L3- I1-Ir.sub.2(L3) I1-Ir.sub.2(L3-4Br) 93% 4Br) 5 equiv. NBS 0.01 equiv. HBr (aq) I2-Ir.sub.2(L3- I2-Ir.sub.2(L3) I2-Ir.sub.2(L3-4Br) 91% 4Br) 5 equiv. NBS I1-Ir.sub.2(L16- 4Br) I1- Ir.sub.2(L16) 90% I1-Ir.sub.2(L3-4Br) 5 equiv. NBS I2-Ir.sub.2(L16- I2- I2-Ir.sub.2(L16-4Br) 88% 4Br) Ir.sub.2(L16) 5 equiv. NBS 0.01 equiv. HBr (aq) I1-Ir.sub.2(L19- 4Br) I1- Ir.sub.2(L19) 84% I1-Ir.sub.2(L19-4Br) 5 equiv. NBS I2-Ir.sub.2(L19- I2- I2-Ir.sub.2(L19-4Br) 88% 4Br) Ir.sub.2(L19) 5 equiv. NBS I1-Ir.sub.2(L23- 4Br) I1- Ir.sub.2(L23) 86% I1-Ir.sub.2(L23-4Br) 4.5 equiv. NBS I2-Ir.sub.2(L23- I2- I2-Ir.sub.2(L23-4Br) 85% 4Br) Ir.sub.2(L23) 4.5 equiv. NBS I1-Ir.sub.2(L26- 4Br) I1- Ir.sub.2(L26) 87% I1-Ir.sub.2(L26-4Br) 5.5 equiv. NBS 0.02 equiv. HBr (aq) I2-Ir.sub.2(L26- I2- I2-Ir.sub.2(L26-4Br) 92% 4Br) Ir.sub.2(L26) 5.5 equiv. NBS 0.02 equiv. HBr (aq)

(100) 2) Suzuki Coupling with the Brominated Iridium Complexes:

(101) Variant A, Biphasic Reaction Mixture:

(102) To a suspension of 10 mmol of a brominated complex, 12-20 mmol of boronic acid or boronic ester per Br function and 60-100 mmol of tripotassium phosphate in a mixture of 300 ml of toluene, 100 ml of dioxane and 300 ml of water are added 0.6 mmol of tri-o-tolylphosphine and then 0.1 mmol of palladium(II) acetate, and the mixture is heated under reflux for 16 h. After cooling, 500 ml of water and 200 ml of toluene are added, the aqueous phase is removed, and the organic phase is washed three times with 200 ml of water and once with 200 ml of saturated sodium chloride solution and dried over magnesium sulfate. The mixture is filtered through a Celite bed and washed through with toluene, the toluene is removed almost completely under reduced pressure, 300 ml of methanol are added, and the precipitated crude product is filtered off with suction, washed three times with 50 ml each time of methanol and dried under reduced pressure. The crude product is columned on silica gel in an automated column system (Torrent from Semrau). Subsequently, the complex is purified further by hot extraction in solvents such as ethyl acetate, toluene, dioxane, acetonitrile, cyclohexane, ortho- or para-xylene, n-butyl acetate etc. Alternatively, it is possible to recrystallize from these solvents and high boilers such as dimethylformamide, dimethyl sulfoxide or mesitylene. The metal complex is finally heat-treated. The heat treatment is effected under high vacuum (p about 10.sup.−6 mbar) within the temperature range of about 200-300° C.

(103) Variant B, Monophasic Reaction Mixture:

(104) To a suspension of 10 mmol of a brominated complex, 12-20 mmol of boronic acid or boronic ester per Br function, 100-180 mmol of a base (potassium fluoride, tripotassium phosphate (anhydrous, monohydrate or trihydrate), potassium carbonate, cesium carbonate etc.) and 50 g of glass beads (diameter 3 mm) in 100-500 ml of an aprotic solvent (THF, dioxane, xylene, mesitylene, dimethylacetamide, NMP, DMSO, etc.) is added 0.2 mmol of tetrakis(triphenylphosphine)palladium(0) [14221-01-3], and the mixture is heated under reflux for 24 h. Alternatively, it is possible to use other phosphines such as triphenylphosphine, tri-tert-butylphosphine, SPhos, XPhos, RuPhos, XanthPhos, etc. in combination with Pd(OAc).sub.2, the preferred phosphine:palladium ratio in the case of these phosphines being 3:1 to 1.2:1. The solvent is removed under reduced pressure, the product is taken up in a suitable solvent (toluene, dichloromethane, ethyl acetate, etc.) and purification is effected as described in Variant A.

(105) Synthesis of Ir.sub.2100:

(106) ##STR00777##

(107) Variant B:

(108) Use of 20.7 g (10.0 mmol) of I1-Ir(L1-4Br), 9.75 g (80.0 mmol) of phenylboronic acid [98-80-6], 27.6 g (120 mmol) of tripotassium phosphate monohydrate, 116 mg (0.1 mmol) of tetrakis(triphenylphosphine)palladium(0) and 500 ml of dry dimethyl sulfoxide, 100° C., 16 h. Chromatographic separation on silica gel with toluene/heptane (automated column system, Torrent from Axel Semrau), followed by hot extraction five times with toluene. Yield: 9.5 g (5.6 mmol), 46%; purity: about 99.8% by HPLC.

(109) In an analogous manner, it is possible to prepare the following compounds:

(110) TABLE-US-00018 Reactant Variant/ Reaction conditions Ex. Boronic acid Product/hot extractant (HE) Yield Ir.sub.2101 25% HE: ethyl acetate Rh.sub.2100 0 45% HE: toluene Ir.sub.2102 48% HE: o-xylene Ir.sub.2103 44% HE: n-butyl acetate Ir.sub.2104 47% HE: dichloromethane Ir.sub.2105 50% HE: toluene Ir.sub.2106 0 38% Ir.sub.2107 52%

(111) 3) Deuteration of Ir Complexes

Example: Ir.SUB.2.(L7-D12)

(112) ##STR00794##

(113) A mixture of 1 mmol of Ir.sub.2(L7), 1 mmol of sodium ethoxide, 5 ml of methanol-D4 and 80 ml of DMSO-D6 is heated to 120° C. for 2 h. After cooling to 50° C., 1 ml of DCI (10% aqueous solution) is added. The solvent is removed under reduced pressure and the residue is chromatographed with DCM on silica gel. Yield: 0.95 mmol, 95%, deuteration level >95%.

(114) In an analogous manner, it is possible to tetradeuterate the compounds Ir.sub.2(L11), Ir.sub.2(L12) and Ir.sub.2(L20):

Device Examples

(115) Production of the OLEDs

(116) The complexes of the invention can be processed from solution and lead, compared to vacuum-processed OLEDs, to much more easily producible OLEDs having properties that are nevertheless good. There are already many descriptions of the production of completely solution-based OLEDs in the literature, for example in WO 2004/037887. There have likewise been many prior descriptions of the production of vacuum-based OLEDs, including in WO 2004/058911. In the examples discussed hereinafter, layers applied in a solution-based and vacuum-based manner are combined within an OLED, and so the processing up to and including the emission layer is effected from solution and in the subsequent layers (hole blocker layer and electron transport layer) from vacuum. For this purpose, the previously described general methods are matched to the circumstances described here (layer thickness variation, materials) and combined as follows. The general structure is as follows: substrate/ITO (50 nm)/hole injection layer (HIL)/hole transport layer (HTL)/emission layer (EML)/hole blocker layer (HBL)/electron transport layer (ETL)/cathode (aluminum, 100 nm). Substrates used are glass plates coated with structured ITO (indium tin oxide) of thickness 50 nm. For better processing, they are coated with PEDOT:PSS (poly(3,4-ethylenedioxy-2,5-thiophene) polystyrenesulfonate, purchased from Heraeus Precious Metals GmbH & Co. KG, Germany). PEDOT:PSS is spun on from water under air and subsequently baked under air at 180° C. for 10 minutes in order to remove residual water. The hole transport layer and the emission layer are applied to these coated glass plates. The hole transport layer used is crosslinkable. A polymer of the structure shown below is used, which can be synthesized according to WO 2010/097155 or WO 2013/156130:

(117) ##STR00795##

(118) The hole transport polymer is dissolved in toluene. The typical solids content of such solutions is about 5 g/l when, as here, the layer thickness of 20 nm which is typical of a device is to be achieved by means of spin-coating. The layers are spun on in an inert gas atmosphere, argon in the present case, and baked at 180° C. for 60 minutes.

(119) The emission layer is always composed of at least one matrix material (host material) and an emitting dopant (emitter). In addition, mixtures of a plurality of matrix materials and co-dopants may occur. Details given in such a form as TMM-A (92%):dopant (8%) mean here that the material TMM-A is present in the emission layer in a proportion by weight of 92% and dopant in a proportion by weight of 8%. The mixture for the emission layer is dissolved in toluene or optionally chlorobenzene. The typical solids content of such solutions is about 17 g/I when, as here, the layer thickness of 60 nm which is typical of a device is to be achieved by means of spin-coating. The layers are spun on in an inert gas atmosphere, argon in the present case, and baked at 150° C. for 10 minutes. The materials used in the present case are shown in table 1.

(120) TABLE-US-00019 TABLE 1 EML materials used

(121) The materials for the hole blocker layer and electron transport layer are applied by thermal vapor deposition in a vacuum chamber. The electron transport layer, for example, may consist of more than one material, the materials being added to one another by co-evaporation in a particular proportion by volume. Details given in such a form as ETM1:ETM2 (50%:50%) mean here that the ETM1 and ETM2 materials are present in the layer in a proportion by volume of 50% each. The materials used in the present case are shown in table 2.

(122) TABLE-US-00020 TABLE 2 HBL and ETL materials used 00

(123) The cathode is formed by the thermal evaporation of a 100 nm aluminum layer. The OLEDs are characterized in a standard manner. The EML mixtures and structures of the OLED components examined are shown in table 3 and 4. The corresponding results are found in table 5.

(124) TABLE-US-00021 TABLE 3 EML mixtures of the OLED components examined Matrix A Co-matrix B Co-dopant C Dopant D Ex. material % material % material % material % E-1 A-1 30 B-1 45 C-1 17 I1-Ir.sub.2(L1)  8 E-2 A-1 30 B-1 34 C-1 30 I1-Ir.sub.2(L19)  6 E-3 A-1 30 B-1 30 C-1 30 Ir.sub.2104 10 E-4 A-1 40 B-1 40 — — I1-Ir.sub.2(L19) 20

(125) TABLE-US-00022 TABLE 4 Structure of the OLED components examined HIL HTL EML HBL ETL Ex. (thickness) (thickness) thickness (thickness) (thickness) E-1 PEDOT HTL2 60 nm ETM-1 ETM-1(50%):ETM-2 (20 nm) (20 nm) (10 nm) (50%) (40 nm) E-2 PEDOT HTL2 70 nm ETM-1 ETM-1(50%):ETM-2 (60 nm) (20 nm) (10 nm) (50%) (40 nm) E-3 PEDOT HTL2 60 nm ETM-1 ETM-1(50%):ETM-2 (60 nm) (20 nm) (10 nm) (50%) (50 nm) E-4 PEDOT HTL2 70 nm ETM-1 ETM-1(50%):ETM-2 (60 nm) (20 nm) (10 nm) (50%) (40 nm)

(126) TABLE-US-00023 TABLE 5 Results for solution-processed OLEDs (measured at a brightness of 1000 cd/m.sup.2) EQE Ex. [%] CIEx CIEy E-1 19.1 0.46 0.53 E-2 17.8 0.65 0.35 E-3 17.5 0.66 0.34 E-4 17.6 0.67 0.33

(127) Analogously to example E-4 (table 3), it is also possible to use the compounds of the invention listed hereinafter to produce OLED devices: I1-Rh.sub.2(L1), I2-Rh.sub.2(L1), I1-Ir.sub.2(L2), I2-Ir.sub.2(L2), I1-Ir.sub.2(L3), I2-Ir.sub.2(L3), I1-Ir.sub.2(L4), I2-Ir.sub.2(L4), I1-Ir.sub.2(L5), I2-Ir.sub.2(L5), I1-Ir.sub.2(L6), I2-Ir.sub.2(L6), I1-Ir.sub.2(L7), I2-Ir.sub.2(L7), I1-Ir.sub.2(L8), I2-Ir.sub.2(L8), I1-Ir.sub.2(L9), I2-Ir.sub.2(L9), I1-Ir.sub.2(L10), I2-Ir.sub.2(L10), Ir.sub.2(L11), Ir.sub.2(L12), I1-Ir.sub.2(L13), I2-Ir.sub.2(L13), I1-Ir.sub.2(L14), I2-Ir.sub.2(L14), I1-Ir.sub.2(L15), I2-Ir.sub.2(L15), I1-Ir.sub.2(L16), I2-Ir.sub.2(L16), I1-Ir.sub.2(L17), I2-Ir.sub.2(L17), I1-Ir.sub.2(L18), I2-Ir.sub.2(L18), I2-Ir.sub.2(L19), Ir.sub.2(L20), I1-Ir.sub.2(L21), I2-Ir.sub.2(L21), I1-Ir.sub.2(L22), I2-Ir.sub.2(L22), I1-Ir.sub.2(L23), I2-Ir.sub.2(L23), I1-Ir.sub.2(L24), I2-Ir.sub.2(L24), I1-Ir.sub.2(L25), I2-Ir.sub.2(L25), I1-Ir.sub.2(L26), I2-Ir.sub.2(L26), I1-Ir.sub.2(L27), I2-Ir.sub.2(L27), Ir.sub.2(L28), Ir.sub.2(L29), Ir.sub.2(L7-D12), Ir.sub.2101, Rh.sub.2100, Ir.sub.2102, Ir.sub.2103, Ir.sub.2105, Ir.sub.2106, Ir.sub.2107.

(128) These OLED devices show intense and long-lived yellow to red electroluminescence.