Electroluminescent iridium compound with fluorinated phenylpryidine, phenylpyrimidine, and phenylquinoline and device made with such compound

The present invention relates to fluorinated phenylpyridine, phenylpyrimidine and phenylquinoline. This also relates to electronic devices in which the active layer contains an electroluminescent Ir (III) complex.

This application claims priority over US Patent Provisional Application Nos. 60/215362 (filed June 30, 2000) and US Patent Application No. 60/224273 (August 10, 2000) PCT / US01 / 20539. This is a divisional application based on Japanese Patent Application No. 2002-507959 (domestic transition date: January 6, 2003), which is a domestic transition of issue (filed on June 27, 2001).

Organic electronic devices that emit light, such as light emitting diodes that make up display devices, exist in various types of electronic devices. In all such devices, the organic active layer is sandwiched between the two electrical contact layers. At least one of the electrical contact layers is light transmissive so that light can pass through the electrical contact layer. The organic active layer emits light through the light-transmitting electrical contact layer when electricity is applied across the electrical contact layer.

It is well known that organic electroluminescent compounds are used as active ingredients in light emitting diodes. Simple organic molecules such as anthracene, thiadiazole derivatives and coumarin derivatives are known to exhibit electroluminescence. Semi-conductive conjugated polymers are similarly disclosed in Friend et al. U.S. Pat. No. 5,247,190, Heeger et al., U.S. Pat. No. 5,408,109 and Nakano et al., Published European Patent Application No. 443,861. Has been used as an electroluminescent ingredient. Trivalent metal ions, especially complexes of ammonium and 8-hydroxyquinolates, have been widely used as electroluminescent components, as disclosed, for example, in Tang et al., US Pat. No. 5,552,678.

Burrows and Thompson reported that fac-tris (2-phenylpyridine) iridium can be used as an active ingredient in organic luminescent devices (Appl. Phys. Lett. 1999, 75.4.). Performance is maximized when the iridium compound is present in the host conductive material. The active layer of Thompson is fac-tris [2- (4', 5'-dichlorophenyl) pyridine-C.¹², N] Further reported on devices that are poly (N-vinylcarbazole) doped with iridium (III) (Polymer Preprints 2000, 41 (1), 770).

<p><patcit num="1"><text>U.S. Pat. No. 5,247,190</text></patcit><patcit num="2"><text>U.S. Pat. No. 5,408,109</text></patcit><patcit num="3"><text>European Patent Application Publication No. 443,861</text></patcit><patcit num="4"><text>U.S. Pat. No. 5,552,678</text></patcit></p>

<p><nplcit num="1"><text>Appl. Phys. Lett. 1999, 75.4.</text></nplcit><nplcit num="2"><text>Polymer Preprints 2000, 41 (1), 770</text></nplcit><nplcit num="3"><text>Synlett, 1999, 45-48</text></nplcit></p>

<p> However, there is a continuing need for electroluminescent compounds that show improved efficiency.</p>

<p> The present invention is directed to iridium compounds (commonly referred to as "Ir (III) compounds") having at least two phenylpyridine ligands with at least one fluorinated or fluorinated group on the ligand. There is. The iridium compound has the following first chemical formula. IrL^aL^{b b}L^c_xL'_yL''_z (1st chemical formula) In the ceremony, x = 0 or y + z = 0, and z = 0 when y = 2, x = 0 or 1, y = 0, 1 or 2, and z = 0 or 1. ; L'= bidentate ligand or monodentate, provided that y + z = 2 when L'is a monodentate ligand and z = 0 when L'is a bidentate ligand. It is a ligand and not phenylpyridine, phenylpyrimidine or phenylquinoline; L'' is a monodentate ligand and not phenylpyridine and phenylpyrimidine or phenylquinoline; L^a, L^{b b}And L^cAre similar or different from each other, L^a, L^{b b}And L^cEach of</p><p><chemistry num="1"><img file="JP2012167124A_D0001.tif" /></chemistry></p><p>It has the structure (I), and in the formula, R₁-R₄And R₅-R₈Adjacent pairs of can be joined to form a 5- or 6-membered ring, R₁-R₈At least one of F, C_nF_{2n + 1}, OC_nF_{2n + 1}And OCF₂Selected from X, in the formula, n = 1-6, X = H, Cl or Br, R when A = N₁A = C or N, provided that does not exist.</p><p> In another embodiment, the invention is directed to substituted 2-phenylpyridine, phenylpyrimidine and phenylquinoline precursor compounds that make the Ir (III) compounds described above. The precursor compound has the following structures (II) and (III).</p><p><chemistry num="2"><img file="JP2012167124A_D0002.tif" /></chemistry></p><p>(In the ceremony, A and R₁-R₈Is as defined in structure (I) above, R₉Is H. )</p><p><chemistry num="3"><img file="JP2012167124A_D0003.tif" /></chemistry></p><p>(In the ceremony, R₁₀-R₁₉At least one of them is F, C_nF_{2n + 1}, OC_nF_{2n + 1}And OCF₂Selected from X, n = 1-6, X = H, Cl or Br, R₂₀Is H).</p><p> It can be seen that there is free rotation around the phenyl-pyridine, phenyl-pyrimidine and phenyl-quinoline bonds. However, in the discussion of this book, the compounds are described with respect to one orientation.</p><p> In another embodiment, the invention is directed to an organic electronic device having at least one light emitting layer comprising the Ir (III) compound described above or a combination of the Ir (III) compounds described above.</p><p> As used herein, the term "compound" is intended to mean an uncharged substance consisting of molecules further composed of atoms that cannot be separated by physical means. The term "ligand" is intended to mean a molecule, ion or atom attached to the coordination sphere of a metal ion. The term "complex", when used as a noun, is intended to mean a compound having at least one ion and at least one ligand. The term "group" is intended to mean a portion of a compound, such as a ligand within a complex or a substituent within an organic compound. The word "facial" is a complex Ma with octahedral geometry, where all three "a" groups are adjacent, i.e. at the corner of one side of the octahedron.₃b b₃Is intended to mean one isomer of.</p>

<figref num="1">It is a schematic diagram of a light emitting device (LED).</figref><figref num="2">It is a schematic diagram of the LED test equipment.</figref>

The Ir (III) compound of the present invention is the above-mentioned first chemical formula Ir (III) L.^aL^{b b}L^c_xL''_yHave.

The Ir (III) compounds described above are often referred to as cyclometallated complexes. That is, Ir (III) compounds having the following second chemical formula are also often referred to as bis-cyclometallated complexes. IrL^aL^{b b}L'_yL''_z(2nd chemical formula) (In the ceremony, y, z, L^a, L^{b b}, L'and L'' are as defined in the first chemical formula above.

Ir (III), which has the following third chemical formula, is also often referred to as a tris-cyclometallated complex. IrL^aL^{b b}L^c (Third chemical formula) In the ceremony, L^a, L^{b b}And L^cIs as defined in the first chemical formula above.

Preferred cyclometallated complexes are neutral and nonionic and can be sublimated intact. The thin films of these materials obtained via vacuum deposition exhibit good or excellent electroluminescent properties. The introduction of a fluorine substituent into the ligand on the iridium atom increases both the stability and volatility of the complex. As a result, vacuum deposition can be performed at a low temperature, and decomposition of the complex can be avoided. The introduction of fluorine substituents into the ligand can often reduce the non-radioactive decay rate and the self-quenching phenomenon in the solid state. These reductions can lead to increased electroluminescence efficiency. By varying the substituents with electron donating and electron attracting properties, it is possible to fine-tune the electroluminescent properties of the compound and thus optimize the brightness and efficiency in the electroluminescent device.

Although we do not wish to be bound by theory, it is believed that the emission from the iridium compound is based on the ligand as a result of charge transfer between the metal and the ligand. Therefore, for compounds capable of exhibiting electroluminescence, the above second chemical formula IrL^aL^{b b}L'_yL''_zCompound, and the third chemical formula IrL^aL^{b b}L^cContains the compounds of, where all L in this third chemical formula^a, L^{b b}And L^cIs phenylpyridine, phenylpyridine or phenylquinoline. R of the above structures (I) and (II)₁-R₈Group and structure (III) R₁₀-R₁₉The group can be selected from conventional substituents for alkyl, alkoxy, halogen, nitro, and cyano groups as well as organic compounds such as fluoro, alkyl fluorinated and alkoxy fluorinated groups. These groups can be partially or completely fluorinated (perfluorinated). All R of preferred indium compounds₁-R₈And R₁₆-R₁₉Substituents are fluoro, alkyl perfluorinated (C)_nF_{2n + 1}) And alkyl perfluorinated groups (OC)_nF_{2n + 1}) (Note that the alkyl perfluorinated and alkoxy groups in the formula have 1 to 6 carbon atoms) or the chemical formula (OCF).₂It is selected from the groups of X) (in the formula, X = H, Cl or Br).

The electroluminescent property of the cyclometallated iridium complex is R.₁-R₈And R₁₀-R₁₉It has been found that any one or more of the groups will be lower if they are nitro groups. Therefore, R₁-R₈And R₁₀-R₁₉It is preferable that none of the groups is a nitro group.

The nitrogen-containing ring can be a pyridine ring, a pyrimidine ring or a quinoline ring. It is preferred that at least one fluorinated substituent is on the nitrogen-containing ring (most preferably CF).₃)。

All conventional ligands known for transition metal coordination chemistry are suitable as L'and L''ligands. Examples of bidentate ligands include compounds with two coordinating groups, such as substitutable ethylenediamine and acetylacetonate. Examples of monodentate ligands include chloride and nitrate ions and monoamines. The iridium complex is preferably neutral and sublimable. If a single bidentate ligand is used, it should have a net charge of -1 (-1). If two bidentate ligands are used, they should have a combined net charge of -1 (-1). Bis-cyclometallated complexes can be useful in preparing tris-cyclometallated complexes in which not all ligands are the same.

In a preferred embodiment, the iridium complex has the third chemical formula IrL as described above.^aL^{b b}L^cHave.

In a more preferred embodiment, L^a= L^{b b}= L^cIs. These more preferred compounds preferably exhibit a facial geometry such that the nitrogen atom coordinated to iridium is a trans in relation to the carbon atom coordinated to iridium, as determined by single crystal X-ray diffraction. Often. These more preferred compounds have the following fourth chemical formula. Fac-Ir (L)^a)₃ (4th chemical formula) (In the formula, L^aHas the structure (I) described above).

The compounds also exhibit a meridional geometry in which two of the nitrogen atoms coordinated to iridium are trans to each other. These compounds have the following fifth chemical formula: mer-Ir (L)^a)₃ (5th chemical formula) (In the formula, L^aHas the structure (I) described above).

Examples of the compounds of the above 4th and 5th chemical formulas are shown in Table 1 below.

<tables num="1"><img file="JP2012167124A_D0004.tif" /></tables>

The above-mentioned second chemical formula IrL^aL^{b b}L'_yL''_zExamples of the compounds of are compounds having the following structures (IV), (V), (VI), (IX) and (X), respectively.<u style="single">1-n</u>、<u style="single">1-o</u>、<u style="single">1-p</u>, 1-w and 1-x are included.

<chemistry num="4"><img file="JP2012167124A_D0005.tif" /></chemistry>

<chemistry num="5"><img file="JP2012167124A_D0006.tif" /></chemistry>

The above-mentioned third chemical formula IrL^aL^{b b}L^cThe iridium complex of is generally prepared from the appropriate substituted 2-phenylpyridine, phenylpyrimidine or phenylquinoline. Substituted 2-phenylpyridines as shown in structure (II) above; phenylpyrimidines and phenylquinolines are as described in O. Lohse, P. Thevenin, E. Waldvogel Synlett, 1999, 45-48. Prepared in good to excellent yields using Suzuki coupling of 2-chloropyridine, 2-chloropyrimidine or 2-chloroquinoline substituted with allylboric acid. This reaction is exemplified for pyridine derivatives in which X and Y represent substituents in the following equation (1).

<chemistry num="6"><img file="JP2012167124A_D0007.tif" /></chemistry>

Examples of 2-phenylpyridine and 2-phenylpyrimidine compounds having the above structure (II) are shown in Table 2 below.

<tables num="2"><img file="JP2012167124A_D0008.tif" /></tables>

As an example of the substituted 2-phenylquinoline compound having the above-mentioned structure (II), R₁₇= CF₃And R₁₀-R₁₆And R₁₈-R₂₀Compound with = H<u style="single">2-u</u>There is.

The 2-phenylpyridine, pyrimidine and quinoline thus prepared are used for the synthesis of cyclometallated iridium complexes. Convenient one-step methods have been developed utilizing commercially available iridium trichloride hydrate and silver trifluoroacetate. Generally the reaction is 3 equivalents of AgOCOCF₃In the presence of, with no solvent and with excess 2-phenylpyridine, pyrimidine or quinoline. This reaction is illustrated in equation (2) below for 2-phenylpyridine:

<chemistry num="7"><img file="JP2012167124A_D0009.tif" /></chemistry>

Triscyclometallated iridium complexes are isolated, purified, elemental analyzed,¹H and¹⁹F NMR spectral data and compounds<u style="single">1-b</u>、<u style="single">1-c</u>as well as<u style="single">1-e</u>Was completely characterized by crystalline X-ray diffraction. In some cases, isomer mixtures were obtained. Often, the mixture can be used without isolating the individual isomers.

In some cases, the above-mentioned second chemical formula IrL^aL^{b b}L'_yL''_zThe iridium complex having the above-mentioned third chemical formula IrL^aL^{b b}L^cIt can be isolated from the reaction mixture using the same synthetic procedure as the preparation of the complex with . The complex can also be prepared by first preparing an intermediate iridium dimer having the following structure (VII).

<chemistry num="8"><img file="JP2012167124A_D0010.tif" /></chemistry>

(In the ceremony, B = H, CH₃Or C₂H₅And L^a, L^{b b}, L^cAnd L^dCan be the same or different from each other, L^a, L^{b b}, L^cAnd L^dEach of them has the structure (I) described above) Iridium dimer can generally be prepared by first reacting 2-phenylpyridine, phenylpyrimidine or phenylquinoline with iridium trichloride hydrate and adding NaOB.

One particularly useful iridium dimer is a hydroxoiridium dimer with the following structure (VIII):

<chemistry num="9"><img file="JP2012167124A_D0011.tif" /></chemistry>

This intermediate is compounded by the addition of ethyl acetoacetate.<u style="single">1-p</u>Can be used to prepare.

(Electronic device) The invention also relates to electronic devices that include at least one photoactive layer located between two electrical contact layers, wherein at least one layer contains the iridium complex of the invention. Devices often have additional hole transport and electron transport layers. The standard structure is shown in Figure 1. The device 100 has an anode layer 110 and a cathode layer 150. Adjacent to the anode is layer 120 containing the hole transport material. Adjacent to the cathode is layer 140 containing the electron transport material. There is a photoactive layer 130 between the hole transport layer and the electron transport layer.

Depending on the field of application of the device 100, the photoactive layer 130 is associated with a light emitting layer activated by the applied voltage (eg, in the case of a light emitting diode or light emitting electrochemical cell), in response to radiant energy and with an applied bias voltage. It can be a material layer (eg, in the case of a photodetector) that produces a signal with or without it. Examples of photodetector mechanisms include photoconducting cells, photoconducting cells, photoswitches, phototransistors and phototubes and photovoltaic cells. These terms are described in Markus, John, Electronics and Nucleonics Dictionary, 470 and 476 (Magrow Hill, Inc. 1996).

The iridium compound of the present invention is useful as a photoactive material in layer 130 or as an electron transport material in layer 140. Preferably, the iridium complex of the present invention is used as a light emitting material in a diode. In these fields of application, the fluorinated compounds of the invention need not be in solid matrix diluents to be effective. A layer in which 20% by weight or more and a maximum of 100% is an iridium compound based on the total weight of the layers can be used as the light emitting layer. This is with the non-fluorinated iridium compound or tris (2-phenylpyridine) iridium (III), which was found to achieve maximum efficiency when present in the light emitting layer in an amount of only 6-8% by weight. Is in contrast. This was necessary to reduce the self-quenching effect. Along with the iridium compound, additional materials may also be present in the light emitting layer. For example, a fluorescent dye may be present to change the color of the emission. It is also possible to add a diluent. The diluent may be a polymer material such as poly (N-vinylcarbasol) and polysilane. It can also be a small molecule such as 4,4'-N, N'-dicarbazolebiphenyl or a tertiary aromatic amine. When diluents are used, the iridium compound is generally present in small amounts, usually less than 20% by weight, preferably less than 10% by weight, based on the total weight of the layers.

In some cases, the iridium complex can also be present in multiple isomer forms, otherwise a mixture of different complexes may be present. In the above discussion of OLEDs, it will be found that the term "iridium compound" is intended to include mixtures of compounds and / or isomers.

In order to realize a high efficiency LED, the HOMO (highest occupied molecular orbital) of the hole transport material should be aligned with the work function of the anode, and the LUMO (lowest unoccupied molecular orbital) of the electron transport material should be aligned. It should be aligned with the work function of the cathode. The chemical compatibility and sublimation temperature of the material are also important considerations in choosing an electron and hole transport material.

The other layers of the OLED may be made of any material known to be useful in such layers. The anode 110 is a particularly efficient electrode for injecting positive charge carriers. It may be made of, for example, a metal, a mixed metal, an alloy, a metal oxide or a material containing a mixed metal oxide, or it may be a conductive polymer. Suitable metals include group 11 metals, groups 4, groups 5 and 6 metals and groups 8-10 transition metals. If the anode must be light transmissive, mixed metal oxides of groups 12, 13 and 14 metals such as indium, tin-oxide are commonly used. Overall, the IUPAC numbering system is used, where the groups from the periodic table are numbered 1-18 from left to right (CRC Chemistry and Physics Handbook), 2000, 81st edition). Anode 110 is also like polyaniline as described in "Flexible Light Emitting Diodes Made from Soluble Conductive Polymers" Nature Vol. 357, p477-479 (June 11, 1992). Organic materials may also be included. At least one of the anode and cathode should be at least partially transparent so that the light produced can be observed.

Examples of hole transport materials for layer 120 are summarized, for example, in Y. Wang's Kirk-Othmer Encyclopedia of Chemical Technology, 4th Edition, Vol. 18, p837-860, 1996. Both hole-transporting molecules and polymers can be used. Commonly used hole transport molecules are N, N'-diphenyl-N, N'-bis (3-methylphenyl)-[1,1'-biphenyl] -4,4'-diamine (TPD), 1 , 1-bis [(di-4-tolylamino) phenyl] cyclohexane (TAPC), N, N'-bis (4-methylphenyl) -N, N'-bis (4-ethylphenyl)-[1,1' -(3,3'-dimethyl) biphenyl] -4,4'-diamine (ETPD), tetrakis- (3-methylphenyl) -N, N, N', N'-2,5-phenylenediamine (PDA) , -Phenyl-4-N, N-diphenylaminostyrene (TPS), p- (diethylamino) -benzaldehyde diphenylhydrazone (DEH), triphenylamine (TPA), bis [4- (N, N-diethylamino) -2- Methylphenyl] (4-Methylphenyl) methane (MPMP), 1-Phenyl-3- [p- (diethylamino) styryl] -5- [p- (diethylamino) phenyl] pyrazoline (PPR or DEASP), 1,2- Trans-bis (9H-carbazol-9-yl) cyclobutane (DCZB), N, N, N', N'-tetrakis (4-methylphenyl)-(1,1'-biphenyl) -4,4'-diamine (TTB), porphyrin compounds such as copper phthalocyanine. Commonly used whole transport polymers are polyvinylcarbasol, (phenylmethyl) polysilane and polyaniline. It is also possible to obtain a hole-transporting polymer by doping a polymer such as polystyrene and polycarbonate with a hole-transporting molecule such as those described above.

An example of an electron transport material for layer 140 is tris (8-hydroxyquinolato) aluminum (Alq).₃), 2,9-Dimethyl-4,7-diphenyl-1,10-phenanthroline (DDPA) or 4,7-diphenyl-1,10-phenanthroline (DPA), which are phenanthroline-based compounds; and 2- (4- (4- Biphenylyl) -5- (4-t-butylphenyl) -1,3,4-oxadiazole (PBD) and 3- (4-biphenylyl) -4-phenyl-5- (4-t-butylphenyl)- Includes azole compounds such as 1,2,4-triazole (TAZ). Layer 140 may serve as a buffer layer or confinement layer to facilitate electron transport and at the same time prevent exciton quenching at the layer interface. Preferably, this layer promotes electron mobility and reduces exciton quenching.

The cathode 150 is a particularly efficient electrode for injecting electrons and negative charge carriers. The cathode can be any metal or non-metal with a lower work function than the anode. The cathode material can be selected from alkali metals of Group 12 metals containing actinides and lanthanides and rare earth elements, Group 1 (eg Li, Cs), Group 2 (alkaline earth) metals. Materials such as aluminum unime, indium, calcium, barium, samarium and magnesium, and combinations thereof can also be used. Similarly, the Li-containing organometallic compound can be adhered between the organic layer and the cathode layer in order to lower the operating voltage.

It is also known to use other layers within organic electronic devices. For example, there is one layer (not shown) between the conductive polymer layer 120 and the active layer 130 to facilitate positive charge transport and / or forbidden bandwidth alignment of the layers or to function as a protective layer. obtain. Similarly, between the active layer 130 and the cathode layer 150, there is an additional layer (not shown) to facilitate or protect negative charge transport and / or forbidden bandwidth matching between layers. Can be done. Layers known in the art can be used. Furthermore, any of the above layers may be made up of two or more layers. Alternatively, part or all of the inorganic anode layer 110, the conductive polymer layer 120, the active layer 130, and the cathode layer 150 can be surface-treated to increase the charge carrier transport efficiency. The choice of material for each component layer is preferably determined by balancing the ultimate goal of providing the device with high device efficiency.

It is also understandable that each functional layer can be made up of multiple layers.

The device can be prepared by sequentially depositing individual layers on a suitable substrate. Substrates such as glass and polymer membranes are available. Conventional vapor deposition techniques such as thermal vapor deposition, chemical vapor deposition, etc. can be used. Alternatively, any conventional coating technique can be used to coat the organic layer from a solution or dispersion in a suitable solvent. In general, the different layers will have a thickness range of 110, 500-5000 Å, preferably 1000-2000 Å; hole transport layer 120, 50-1000 Å, preferably 200-800 Å; light emitting layer. 130, 10 to 1000 Å, preferably 100 to 800 Å; electron transport layer 140, 50 to 1000 Å, preferably 200 to 800 Å; cathode 150, 200 to 10000 Å, preferably 300 to 5000 Å. The location of the electron-hole recombination zone within the device and thus the emission spectrum of the device can be influenced by the relative thickness of each layer. Thus, the thickness of the electron-transport layer should be chosen so that the electron-hole binding zone is within the light emitting layer. The desired ratio of layer thickness will depend on the exact nature of the material used.

It can be seen that the efficiency of devices made of the iridium compounds of the present invention can be further improved by optimizing the other layers within the device. More efficient cathodes such as Ca, Ba or LiF can also be used. Shaped substrates and new transport materials that result in reduced operating voltage or increase quantum efficiency are also available. Additional layers can also be added to adjust the energy levels of the various layers and facilitate electroluminescence.

The iridium complexes of the present invention are often phosphorescent and photoluminescent and may be useful in applications other than OLEDs. For example, organometallic complexes of iridium have been used as oxygen-sensitive indicators, phosphorescent indicators in bioassays, and as catalysts. It is possible to use a biscyclometallated complex to synthesize a triscyclometallated complex in which the third ligand is the same or different.

<p> The following examples exemplify some of the features and advantages of the present invention. These are intended as examples of the present invention and have no limiting meaning. All percentages are weight percentages unless otherwise indicated.</p><p> (Example 1) This example illustrates the preparation of 2-phenylpyridine and 2-phenylpyrimidine used to form iridium compounds.</p><p> The general procedure used is that described in O. Lohse, P. Thevenin, E. Waldvogel Synlett, 1999, 45-48. In a standard experiment, 200 ml of degassed water, 20 g of potassium carbonate, 150 ml of 1,2-dimethoxyethylene, 0.5 g of Pd (PPh).₃)₄A mixture of 0.05 mol of substituted 2-chloropyridine (quinoline or bilimidine) and 0.05 mol of substituted phenylboric acid was refluxed for 16-30 hours (80-90 ° C). The resulting reaction mixture was diluted with 300 ml of water and CH₂Cl₂Extracted with (2 x 100 ml). The combined organic layer is PEG₄It was dried on top and the solvent was removed by vacuum. The liquid product was purified by fractional vacuum distillation. The solid material was recrystallized from hexane. The standard purity of the isolated material was over 98%.</p><p> The starting materials, yields, melting points and boiling points of the new materials are shown in Table 3 below. NMR data and analytical data are shown in Table 4 below.</p><p><tables num="3"><img file="JP2012167124A_D0012.tif" /></tables></p><p><tables num="4"><img file="JP2012167124A_D0013.tif" /></tables></p><p><tables num="5"><img file="JP2012167124A_D0014.tif" /></tables></p><p><tables num="6"><img file="JP2012167124A_D0015.tif" /></tables></p><p> (Example 2) In this example, the above-mentioned fourth chemical formula fac-Ir (L)^a)₃The preparation of the iridium compound of the above is illustrated.</p><p> In standard experiments, IrCl₃ NH₂O (53 ~ 55% Ir), AgOCOCF₃Mixture of (3.1 eq per Ir), 2-allylpyridine (surplus) and (optionally) a small amount of water at 180-195 ° C (oil bath) for 2-8 hours N₂Stir vigorously under. CH the resulting mixture until the extract is colorless₂Cl₂Thoroughly extracted with. The extract was filtered through a silica column to produce a clear, yellow solution. Evaporation of this solution gave a residue, which was treated with methanol to produce a colored crystalline tris-cyclometallated Ir complex. The complex was separated by filtration, washed with methanol, dried under vacuum and purified by (optionally) crystallization, vacuum sublimation or Soxhlet extraction. Yield: 10-82%. All materials are characterized by NMR spectroscopic data and elemental analysis, the results are shown in Table 5 below. Single crystal X-ray structures were obtained for the three complexes in the series.</p><p> (Compound 1-b) IrCl while slowly raising the temperature (30 minutes) to 185 ° C (oil bath)₃ NH₂O (54% Ir: 508mg), 2- (4-fluorophenyl) -5-trifluoromethylpyridine, compound kk (2.20g), AgOCOCF₃N a mixture of (1.01 g) and water (1 mL)₂Stir vigorously under the stream. After 2 hours at 185-190 ° C, the mixture solidified. The mixture was cooled to room temperature. The solid was extracted with dichloromethane until the extract was decolorized. The combined dichloromethane solution was filtered and evaporated through a short silica column. Methanol (50 mL) was added to the residue and the flask was kept at -10 ° C and left overnight. The yellow precipitate of the tris-cyclometallated complex, compound b, was separated, washed with methanol and dried under vacuum. Yield: 1.07g (82%). X-ray quality crystals of the complex were obtained by slowly cooling the warm solution in 1,2-dichloroemethane.</p><p> (Compound 1-e) IrCl while slowly raising the temperature (15 minutes) to 192 ° C (oil bath)₃ NH₂O (54% Ir: 504 mg), 2- (3-trifluoromethylphenyl) -5-trifluoromethylpyridine, compound bb (1.60 g) and AgOCOCF₃N the mixture of (1.01 g)₂Stir vigorously under the stream. After 6 hours at 190-195 ° C, the mixture solidified. The mixture was cooled to room temperature. The solid was placed on a silica column, which was then washed with a large amount of dichloromethane. The evaporated residue of the filtrate was treated with methanol to produce a yellow solid. Solids were collected and purified by extraction with dichloromethane in a 25-mL Micro-Soxhlet extractor. The yellow precipitate of the tris-cyclometallated complex, compound e, was separated, washed with methanol and dried under vacuum. Yield: 0.59g (39%). X-ray quality crystals of the complex were obtained from the hot 1,2-dichloroethane.</p><p> (Compound 1-d) IrCl for 6 hours and 15 minutes at 190-195 ° C (oil bath)₃ NH₂O (54% Ir: 508 mg), 2- (2-fluorophenyl) -5-trifluoromethylpyridine, compound aa (1.53 g) and AgOCOCF₃N the mixture of (1.01 g)₂Stir vigorously under the stream. The mixture was cooled to room temperature and then extracted with hot 1,2-dichloroethane. The extract was filtered through a short silica column and evaporated. Treatment of the residue with methanol (20 mL) resulted in a precipitate of the desired product, compound d, which was separated by filtration, washed with methanol and dried under vacuum. Yield: 0.63g (49%). X-ray quality crystals of the complex were obtained from dichloromethane / methanol.</p><p> (Compound 1-i) IrCl for 2 hours and 45 minutes at 190-195 ° C (oil bath)₃ NH₂O (54% Ir: 503 mg), 2- (4-trifluoromethoxyphenyl) -5-trifluoromethylpyridine, compound ee (2.00 g) and AgOCOCF₃N the mixture of (1.10g)₂Stir vigorously under the stream. The mixture was cooled to room temperature and then extracted with dichloromethane. The extract was filtered through a short silica column and evaporated. Treatment of the residue with methanol (20 mL) resulted in a precipitate of the desired product, compound i, which was separated by filtration, washed with methanol and dried under vacuum. The yield was 0.86 g. Further, the mother liquor was evaporated and petroleum ether was added to the residue to obtain 0.27 g of a complex. Overall yield: 1.13g (72%).</p><p> (Compound 1-q) IrCl while slowly raising the temperature (30 minutes) to 185 ° C (oil bath)₃ NH₂O (54% Ir: 530mg), 2- (3-methoxyphenyl) -5-trifluorosmethylpyridine (2.50g), AgOCOCF₃N a mixture of (1.12 g) and water (1 mL)₂Stir vigorously under the stream. After 1 hour at 185 ° C, the mixture solidified. The mixture was cooled to room temperature. The solid was extracted with dichloromethane until the extract was decolorized. The combined dichloromethane solution was filtered and evaporated through a short silica column. The residue was washed with hexane and then recrystallized from 1,2 dichloroethane-hexane. Yield: 0.30g.¹⁹F NMR (CD)₂Cl₂, 20 ° C), δ: -63 (s),¹H NMR (CD)₂Cl₂, 20 ° C), δ: 8.1 (1H), 7.9 (1H), 7.8 (1H), 7.4 (1H), 6.6 (2H), 4.8 (3H). From 1,2-dichloroethane-hexane, X-ray quality crystals of the complex (1,2-dichloroethane, hexane solvate) were obtained. This facial complex was orange electroluminescent.</p><p> Compounds in the same way<u style="single">1-a</u>、<u style="single">1-c</u>、<u style="single">1-f ~ 1-h</u>、1-<u style="single">j ~ 1-m and 1-r</u>Was prepared. In the preparation of compound 1-j, the mixture of isomers is R₆Or R₈Obtained with fluorine at any of the positions.</p><p><tables num="7"><img file="JP2012167124A_D0016.tif" /></tables></p><p><tables num="8"><img file="JP2012167124A_D0017.tif" /></tables></p><p> (Example 3) In this example, the above-mentioned second chemical formula IrL^aL^{b b}L^c_xL'_yL''_zIt illustrates the preparation of the iridium complex of.</p><p> (Compound 1-n) IrCl at 190-195 ° C for 4 hours₃ NH₂A mixture of O (54% Ir: 510 mg), 2- (3-trifluoromethylphenyl) -quinoline (1.80 g) and silver trifluoroacetate (1.10 g) was vigorously stirred. The resulting solid was chromatographed on silica with dichloromethane to produce a mixture of dicyclometallated complex and unreacted ligand. Unreacted ligands were removed from the mixture by extraction with warm hexane. After the extract became colorless, a hexane insoluble solid was collected and dried under vacuum. The yield was 0.29 g.¹⁹F NMR: -63.5 (s.6F), -76.5 (s.3F). The structure of this complex was substantiated by single crystal X-ray diffraction studies.</p><p> (Compound 1-o) IrCl at 190 ° C for 1.5 hours₃ NH₂A mixture of O (54% Ir: 500 mg), 2- (2-fluorophenyl) -3-chloro-5-trifluoromethylpyridine (2.22 g), water (0.3 mL) and silver trifluoroacetate (1.00 g). The mixture was stirred at 190 ° C for 1.5 hours. The solid product was chromatographed on silica with dichloromethane to produce 0.33 g of dicyclometallated aquatrifluoroacetato complex, compound lp and 2: 1 co-crystallized adjuvant of unreacted ligand.¹⁹F NMR: -63.0 (9F), -76.5 (3F), -87.7 (2F), -114.4 (1F). The co-crystallized phenylpyridine ligand was removed from dichloromethane-hexane by recrystallization. The structure of the adapter and the complex was proved by a single crystal X-ray diffraction study.</p><p> (Example 4) This example illustrates the preparation of a hydroxoiridium dimer having the structure (VIII) described above.</p><p> IrCl₃ NH₂Reflux a mixture of O (54% Ir: 510 mg), 2- (4-fluorophenyl) -5-trifluoromethylpyridine (725 mg), water (5 mL), and 2-ethoxyethanol (20 mL) for 4 to 5 hours. Stir vigorously below. A solution of NaOH (2.3 g) in water (5 mL) was added, then 20 mL of water was added, and then the mixture was stirred for 2 hours under reflux. The mixture was cooled to room temperature, diluted with 50 mL of water and filtered. The solid was vigorously stirred for 6 hours under reflux with 30 mL of 1,2-dichloroethane and NaOH water (2.2 g in 8 mL of water). The organic solvent was evaporated from the mixture leaving a suspension of orange solid in the aqueous phase. The orange solid was separated by filtration, washed thoroughly with water and dried under vacuum to produce 0.94 g (95%) of iridium hydroxodimer (spectroscopically pure).¹H NMR (CD)₂Cl₂): -1.0 (s, 1H, IrOH), 5.5 (dd, 2H), 6.6 (dt, 2H), 7.7 (dd, 2H), 7.9 (dd, 2H), 8.0 (dd, 2H), 9.1 (d , 2H).¹⁹F NMR (CD)₂Cl₂): -62.5 (s, 3F), -109.0 (ddd, 1F).</p><p> (Example 5) This example illustrates the preparation of a bis-cyclometallated complex from an iridium dimer.</p><p> (Compound 1-p) A mixture of iridium hydroxodimer (100 mg) ethyl acetoacetate (0.075 mL; 4-fold surplus) and dichloromethane (4 mL) from Example 4 was stirred overnight at room temperature. The solution was filtered through a short silica plug and evaporated to give an orange-yellow solid, which was washed with hexane and dried. The yield of the complex was 109 mg (94%).¹H NMR (CD)₂Cl₂): 1.1 (t, CH₃), 3.9 (dm, CH₂), 4.8 (s, CH₃COCH), 5.9 (m), 6.7 (m), 7.7 (m), 8.0 (m), 8.8 (d).¹⁹F NMR (CD)₂Cl₂): -63.1 (s, 3F), -63.2 (s, 3F), -109.1 (ddd, 1F), -109.5 (ddd). Analysis: Calculated: C, 44.9; H, 2.6; N, 3.5. Actual Values C, 44.4; H, 2.6; N, 3.3.</p><p> (Compound 1-w) A solution of hydroxoiridium dimer in THF (6 mL) from Example 4 (0.20 g) was treated with 50 mg of trifluoroacetic acid, filtered through a short silica plug, evaporated to a calculated 0.5 mL, and hexane (8 mL). ) And left overnight. The yellow crystalline solid was separated, washed with hexane and dried under vacuum. Yield (1: 1 THF solvate): 0.24 g (96%).¹⁹F NMR (CD)₂Cl₂, 20 ° C), δ: -63.2 (s, 3F), -76.4 (s, 3F), -107.3 (ddd, 1F).¹H NMR (CD)₂Cl₂, 20 ° C), δ: 9.2 (br s, 1H), 8.2 (dd, 1H), 8.1 (d, 1H), 7.7 (m, 1H), 6.7 (m, 1H), 5.8 (dd, 1H) , 3.7 (m, 2H, THF), 1.8 (m, 2H, THF).</p><p> (Compound 1-x) Trifluoroacetic acid intermediate, compound 1-w (75 mg) and 2- (4-bromophenyl) -5-bromopyridine (130 mg) N₂The mixture was stirred under 150 to 155 ° C for 30 minutes. The resulting solid is cooled to room temperature and CH₂Cl₂Dissolved in. The resulting solution was filtered through silica gel and evaporated. The residue was washed several times with warm hexane and dried under vacuum to leave a yellow, yellow photoluminescent solid. Yield: 74 mg (86%).¹⁹F NMR (CD)₂Cl₂, 20 ° C), δ: -63.1 (s, 3F), -63.3 (s, 3F), -108.8 (ddd, 1F), -109.1 (ddd, 1F).¹H NMR (CD)₂Cl₂, 20 ° C), δ: 8.2 (s), 7.9 (m), 7.7 (m), 7.0 (d), 6.7 (m), 6.2 (dd), 6.0 (dd). The complex is a meridional complex. The nitrogen of the fluorinated ligand was a trans, as confirmed by X-ray analysis.</p><p> (Example 6) In this example, the above-mentioned fifth chemical formula mer-Ir (L)^a)₃It illustrates the preparation of the iridium compound of.</p><p> (Compound 1-s) This complex was synthesized in a manner similar to compound 1-n. According to NMR, TLC and TGA data, the results were a nearly 1: 1 mixture of facial and meridional isomers.</p><p> (Compound 1-t) IrCl while slowly raising the temperature (30-40 minutes) to 165 ° C (oil bath)₃ NH₂O (54% Ir: 0.40g), 2- (3,5-dichlorophenyl) -5-trifluoromethylpyridine (1.40g), AgOCOCF₃N a mixture of (0.81 g) and water (0.5 mL)₂Stir vigorously under the stream. After 40 minutes at 165 ° C, the mixture solidified. The mixture was cooled to room temperature. The solid was extracted with dichloromethane until the extract was decolorized. The combined dichloromethane solution was filtered and evaporated through a short silica column. The residue was thoroughly washed with hexane and dried under vacuum. Yield: 0.53g (49%).¹⁹F NMR (CD)₂Cl₂, 20 ° C), δ: -63.55 (s, 3F), -63.57 (s, 3F), -63.67 (s, 3F), -89.1 (t, 1F), -100.6 (t, 1F), 102.8 ( dd, 1F), -118.6 (ddd, 1F), -119.3 (ddd, 1F), -123.3 (ddd, 1F).¹H NMR (CD)₂Cl₂, 20 ° C), δ: 8.4 (s), 8.1 (m), 7.9 (m), 7.6 (s), 7.5 (m), 6.6 (m), 6.4 (m). As confirmed, it was a meridional complex.</p><p> (Compound 1-u) The complex was prepared and isolated in a manner similar to compound 1-q and then purified by crystallization from 1,2 dichloroethane-hexane. The purified product was 53%. The complex is mer as follows from the NMR data.¹⁹F NMR (CD)₂Cl₂, 20 ° C), δ: -63.48 (s, 3F), -63.52 (s, 6F), -105.5 (ddd, 1F), -105.9 (ddd, 1F), -106.1 (ddd, 1F), -107.4 (t, 1F), -107.9 (t, 1F), -109.3 (t, 1F).¹H NMR (CD)₂Cl₂, 20 ° C), δ: 8.6 (m), 8.3 (s), 8.2 (s), 8.1 (m), 7.9 (m), 7.6 (m), 6.6 (m), 6.4 (m), 6.0 ( m), 5.8 (m).</p><p> (Compound 1-v) This mer-complex was prepared using a trifluoroacetate dicyclometallated intermediate, compounds 1-x and 2- (4-fluorophenyl) -5-trifluoromethylpyridine in a manner similar to compound 1-w. Prepared.¹⁹F NMR (CD)₂Cl₂, 20 ° C), δ: -63.30 (s, 3F), -63.34 (s, 3F), -63.37 (s, 3F), -108.9 (ddd, 1F), -109.0 (ddd, 1F), -109.7 (ddd, 1F).¹H NMR (CD)₂Cl₂, 20 ° C), δ: 8.3-7.6 (m), 6.7 (m), 6.6 (dd), 6.3 (dd), 6.0 (dd). This yellow-luminescent meridional complex was isomerized to a green luminescent facial isomer, compound 1-b, at the time of sublimation at 1 atm.</p><p> (Example 7) This example illustrates the formation of an OLED using the iridium complex of the present invention.</p><p> Thermal evaporation techniques were used to produce thin film OLED devices containing a hole transport layer (HT layer), an electroluminescent layer (EL layer) and at least one electron transport layer (ET layer). An Edward Auto 306 evaporator with an oil diffusion pump was used. Basic vacuum is 10 for all thin film deposits^-6 It was within the range of torr. The adherence chamber was capable of adhering five different membranes without the need to interrupt the vacuum.</p><p> A glass substrate coated with indium tin oxide (ITO) with an ITO layer of approximately 1000-2000 Å was used. To form the first electrode pattern, the substrate was first patterned by etching and removing unwanted ITO regions with an HCl solution of IN. The patterned ITO substrate was then ultrasonically cleaned in aqueous detergent solution. Then, the substrate was first rinsed with purified water and then degreased with toluene vapor for up to 3 hours.</p><p> The cleaned and patterned ITO substrate is then placed in a vacuum chamber and the chamber is 10^-6Pumped down to torr. The substrate was then further cleaned using oxygen plasma for about 5-10 minutes. After cleaning, the multiple layers of the thin film were sequentially adhered onto the substrate by thermal evaporation. Finally, a patterned metal electrode of Al was applied through a mask. The thickness of the film was measured during adhesion using a crystal monitor (Sycon STC-200). All film thicknesses reported in the examples are nominal values calculated assuming a density of adhered material of 1. The finished OLED device was then removed from the vacuum chamber and immediately characterized without encapsulation.</p><p> A summary of device layers and thicknesses is given in Table 6. In all cases, the anode was ITO as described above and the cathode was Al with a thickness in the range of 700-760 Å. Two electron transport layers were used in some specimens. The first shown layer was applied adjacent to the EL layer.</p><p><tables num="9"><img file="JP2012167124A_D0018.tif" /></tables></p><p><tables num="10"><img file="JP2012167124A_D0019.tif" /></tables></p><p> OLED specimens are characterized by measuring their (1) current-voltage (IV) curves, (2) electroluminescence radiance-voltage relationship, and (3) electroluminescence spectrum-voltage relationship. It was. The instrument 200 used is shown in FIG. The IV curve of the OLED sample 200 was measured with Keithley source measurement unit type 237, 280. Electroluminescence radiance (Cd / m²The relationship between unit) and voltage was measured using the Minolta LS-110 luminescence meter 210 while scanning the voltage with the Keithley SMU. The electroluminescence spectrum was obtained by condensing with a pair of lenses 230 through an electronic shutter 240, dispersed through a spectrograph 250, and then measured by a diode array detector 260. All three measurements were taken simultaneously and controlled by computer 270. The efficiency of a device at a voltage is determined by dividing the electroluminescence radiance of the LED by the current density required to run the device. The unit is Cd / A.</p><p> The results are shown in Table 7 below:</p><p><tables num="11"><img file="JP2012167124A_D0020.tif" /></tables></p><p><tables num="12"><img file="JP2012167124A_D0021.tif" /></tables></p><p> The peak efficiency is the best indicator of the value of the electroluminescent compound in the device. It gives a measure of how many electrons must be input into the device (radiance) to emit a certain number of photons. It is a fundamentally important number that reflects the inherent efficiency of the luminescent material. This is also important for practical applications, as higher efficiency means that less electrons are needed to achieve the same radiance, which in turn means lower power consumption. is there. More efficient devices also tend to have a longer lifetime because the injected electrons are converted to photons at a higher rate instead of generating heat or causing unwanted chemical side reactions. Most of the iridium complexes of the present invention have much higher peak efficiency than the parent fac-tris (2-phenylpyridine) iridium complex. Complexes with lower efficiencies can also find utility as phosphorescent or photoluminescent materials or as catalysts, as described above.</p>

100 devices 110 Anode layer Layer containing 120 hole transport material 130 Photoactive layer 140 Layer containing electron transport material 150 Cathode layer 200 appliances 210 luminescence meter 230 lens 240 electronic shutter 250 spectrograph 260 diode array detector 270 computer