Biphenyl-metal complexes-monomeric and oligomeric triplet emitters for oled applications

Abstract

The present invention relates to light-emitting devices and novel emitter materials as well as emitter systems and, in particular, organic light-emitting devices (OLEDs). In particular, the invention relates to the use of luminescent complexes as emitters in such devices.

1 - 74 . (canceled) 
   
   
       75 . An oligomer comprising at least one complex of the formula (I)
   (s-bph)ML  (I)   in which M represents Pt(II), Rh(I), Ir(I), Pd(II) or Au(III),   L represents a bidentate ligand or   L=X 2 , where each X, independently, represents a monodentate ligand, and   wherein optionally L or optionally at least one X or optionally both L and at least one X contain a polymerizable group,   s-bph represents a ligand which has an Ar—Ar group, where Ar represents an aromatic ring system.   
   
   
       76 . A light-emitting device comprising
 (i) an anode,   (ii) a cathode and   (iii) an emitter layer arranged between and in direct or indirect contact with the anode and the cathode, comprising at least one of the oligomer according to  claim 75  used as an emitter.   
   
   
       77 . The light-emitting device according to  claim 76 ,
 wherein the proportion of complexes of the formula (I) in the emitter layer is greater than 10% by weight, based on the total weight of the emitter layer and L represents a bidentate ligand or   L=X 2 , where each X, independently, represents a monodentate ligand.   
   
   
       78 . The light-emitting device according to  claim 77 ,
 wherein the proportion of complexes of the formula (I) in the emitter layer is greater than 80% by weight based on the total weight of the emitter layer.   
   
   
       79 . The light-emitting device according to  claim 77 ,
 wherein the proportion of complexes of the formula (I) in the emitter layer is greater than 95% by weight based on the total weight of the emitter layer.   
   
   
       80 . The light-emitting device according to  claim 77 ,
 wherein   L=X 2 , where each X is selected, independently, from CO, CNR, NCR, RN═CR′, SCNR, NCSR, NCOR, CN, SCN − , OCN − , F − , Cl − , Br − , I − ,  − CH═CRR′,  − C≡CR, alkyl, aryl, heteroaryl groups,  − OR,  − SR,  − SeR,  − NR 2 ,  − PR 2 ,  − SiR 3 , where R and R′ each, independently of one another, represent H, alkyl, aryl, heteroaryl, alkenyl, alkynyl, halogen, —NR″ 2 , —PR″ 2 , —OR″ or —SR″, where R″ represents H, alkyl, aryl, heteroaryl, alkenyl or alkynyl, where R and R′ may also be linked to one another.   
   
   
       81 . The light-emitting device according to  claim 77 ,
 wherein the emitter comprises the compound (bph)Pt(CO) 2 , (d t Bubph)Pt(CO) 2  or (tmbph)Pt(CO) 2 .   
   
   
       82 . The light-emitting device according to  claim 77 ,
 wherein   L represents a bidentate ligand selected from CN—B—NC 2  NC—B—CN, diimines, acetylacetonate, [RN—CR′═CH—CR′═NR] − , [pz 2 BH 2 ] −  (pz=pyrazolyl), [O—B—O] 2− , [S—B—S] 2− , [Se—B—Se] 2− , [RN—B—NR] 2− , 2,2′-biphenylene, [CH═CR—B—CR═CH] 2−  or [C≡C—B—C≡C] 2− ,   where B is a bridging group, which is an alkylene or arylene group, which is optionally substituted or optionally contains at least one heteroatom.   
   
   
       83 . The light-emitting device according to  claim 77 , wherein complexes of the formula (I) are present in the emitter layer in a columnar structure. 
   
   
       84 . The light-emitting device according to  claim 77 , wherein at least two different complexes of the formula (I) are present in the columnar structure. 
   
   
       85 . The light-emitting device according to  claim 77 , wherein the complex of the formula (I) in the emitter layer is bonded to a polymer. 
   
   
       86 . The light-emitting device according to  claim 85 , wherein the bonding to the polymer takes place via polymerizable groups of the ligands L. 
   
   
       87 . The light-emitting device according to  claim 86 ,
 wherein the complex of the formula (I) (s-bph)ML is formed from a complex of the formula (III)
   (s-bph)ML 1   (III), 
   
     in which L′ represents a bidentate ligand which has a polymerizable group. 
   
   
       88 . The light-emitting device according to  claim 87 , wherein
 L 1  has the formula   
     
       
         
         
             
             
         
       
     
     in which R represents alkyl, aryl, alkoxy, phenoxy, alkylamine or arylamine. 
   
   
       89 . The light-emitting device according  claim 87 , wherein monomers of the formula (III) are applied and subsequently polymerized. 
   
   
       90 . The light-emitting device according to  claim 76 , wherein M in formula (I) represents Pt(II). 
   
   
       91 . The light-emitting device according to  claim 76 , which further comprises a hole-conductor layer or/and an electron-conductor layer. 
   
   
       92 . The light-emitting device according to  claim 76 , which further comprises a CsF or LiF interlayer. 
   
   
       93 . The light-emitting device according to  claim 76 , wherein the device is arranged on a substrate. 
   
   
       94 . The light-emitting device according to  claim 76 , wherein the device is arranged on a glass substrate. 
   
   
       95 . The light-emitting device according to  claim 76 , wherein the complex present in the emitter layer is a triplet emitter. 
   
   
       96 . The light-emitting device according to  claim 95 , wherein the emitter layer comprises complexes of the formula (I) in a concentration of 1 to 10% by weight, based on the total weight of the emitter layer. 
   
   
       97 . The light-emitting device according to  claim 76 , wherein s-bph represents the formula (II) 
     
       
         
         
             
             
         
       
     
     wherein R 1  to R 8  each, independently of one another, represent H, alkyl, aryl, heteroaryl, alkenyl, alkynyl, halogen, —NR 2 , —PR 2 , —OR or —SR,
 wherein R is H, alkyl, aryl, heteroaryl, alkenyl or alkynyl, 
 wherein the radicals R 1  to R 8  may also be linked to one another, 
 and * represent the coordination sites of the ligand. 
 
   
   
       98 . A triplet emitter which comprises the oligomer according to  claim 75 . 
   
   
       99 . A process for the production of a light-emitting device according to  claim 76 , which comprises introducing at least one complex of the formula (I) as oligomer emitter in the emitter layer by means of vacuum sublimation. 
   
   
       100 . A process for the production of a light-emitting device according to  claim 76 , which comprises introducing at least one complex of the formula (I) as oligomer emitter in the emitter layer by a wet-chemical method. 
   
   
       101 . The oligomer according to  claim 75 , which comprises at least two complexes of the formula (I). 
   
   
       102 . The oligomer according to  claim 101 , which comprises at least 10 complexes of the formula (I). 
   
   
       103 . The oligomer according to  claim 101 , wherein the at least two complexes are arranged as a stack. 
   
   
       104 . The oligomer according to  claim 101 , wherein the oligomer has a columnar structure. 
   
   
       105 . The oligomer according to  claim 101 , wherein the oligomer comprises complexes of the formula
   (s-bph)ML*,   
     in which M represents Pt(II), Rh(I), Ir(I), Pd(II) or Au(III),
 s-bph represents a ligand which has an Ar—Ar group, where Ar represents an aromatic ring system and 
 
     L* represents a non-bulky ligand. 
   
   
       106 . The oligomer according to  claim 105 , wherein the oligomer has the structural element
   [(s-bph)ML*] n+ [(s′-bph)M′L*′] m− ,   
     where M and M′ each, independently, represent Pt(II), Rh(I), Ir(I), Pd(II) or Au(III),
 L* and L′ each, independently, represent a bidentate ligand or two monodentate ligands, 
 s-bph and s′-bph each have an Ar—Ar group, where Ar represents an aromatic ring system, and 
 n and m each represent an integer from 0 to 5, where at least one group M′, L*′, s′-bph has been modified to give the groups M, L* and s-bph. 
 
   
   
       107 . The oligomer according to  claim 106 , wherein the M-M separation between two adjacent complexes in the stack is ≦0.37 nm. 
   
   
       108 . The oligomer according to  claim 75  which are further bonded to polymers, and metal-metal interactions form. 
   
   
       109 . The oligomer according to  claim 108 , wherein the metal-metal interactions result in an emission. 
   
   
       110 . A crystalline layer comprising the oligomer according to  claim 101 . 
   
   
       111 . The crystalline layer according to  claim 110  which has a charge-carrier mobility of ≧10 −3  cm 2 /Vs. 
   
   
       112 . Segments of the oligomer according to  claim 75  in a common matrix material which are used for emission layers (EMLs) in OLEDs, for increasing the charge-carrier mobilities. 
   
   
       113 . A complex of the formula A, B or C 
     
       
         
         
             
             
         
       
     
     wherein
 the atoms A 1 -A 8  are each selected, independently, from C, N, O and S, and 
 the ligands R 1 -R 8  each, independently, represent H, CH 3 , C 2 H 5 , CH(CH 3 ) 2 , C(CH 3 ) 3 , CF 3 , C n H 2n+1 , F, CN, OCH 3 , OC n H 2n+1 , SCH 3 , SC n H 2n+1 , N(CH 3 ) 2 , N(C n H 2n+1 )(C n H 2n+1 ), where 
 n=1 to 20, where two or more of the radicals R 1  to R 8  may optionally be linked to one another and thus form additional aliphatic, aromatic or heteroaromatic rings, and 
 the ligands L′ and L 2  each, independently, represent CO, NC—CH 3 , NC—CH(CH 3 ) 2 , NC—C n H 2n+1 , CN—CH 3 , CN—CH(CH 3 ) 2 , CN—C(CH 3 ) 3 , NC—C n H 2n+1 , P(CH 3 ) 3 , As(CH 3 ) 3 , N(CH 3 ) 2 , where the ligands L 1  and L 2  may optionally be parts of a chelate ligand. 
 
   
   
       114 . The complex according to  claim 113  which has one of the following formulas 
     
       
         
         
             
             
         
       
     
   
   
       115 . The complex according to  claim 113  which has one of the following formulas 
     
       
         
         
             
             
         
       
     
   
   
       116 . The complex according to  claim 113  which has one of the following formulas 
     
       
         
         
             
             
         
       
     
     where
 the atoms A 1 -A 8  are each selected, independently, from C, N, O, S, 
 the ligands R 1 -R 8  each, independently, represent H, CH 3 , C 2 Hs, CH(CH 3 ) 2 , C(CH 3 ) 3 , CF 3 , C n H 2n+1 , F, CN, OCH 3 , OC n H 2n+1 , SCH 3 , SC n H 2n+1 , N(CH 3 ) 2 , N(C n H 2n+1 )(C n H 2n+1 ), where n=1 to 20, where two or more of the radicals R 1  to R 8  may be linked to one another and thus form additional aliphatic, aromatic or heteroaromatic rings, and 
 L 1 ∩L 2  represents diphosphine, diamine, diarsine or diene. 
 
   
   
       117 . The oligomer according to  claim 75 , wherein L or at least one X has a C═C group. 
   
   
       118 . The oligomer according to  claim 75 , wherein L represents 
     
       
         
         
             
             
         
       
     
     in which each R, independently, represents H, an alkyl, aryl, alkoxy, aryloxy, alkylamine or arylamine group. 
   
   
       119 . The light-emitting device according to one of  claim 76 , wherein
 L represents a bidentate ligand selected from diphosphines, diamines, diarsines and dienes.   
   
   
       120 . The light-emitting device according to  claim 76 , wherein
 L represents a diphosphine selected from   
     
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       wherein R represents alkyl, aryl, alkoxy, phenoxy, alkylamine or arylamine. 
     
   
   
       121 . The light-emitting device according to  claim 76 , wherein M is Pt(II). 
   
   
       122 . A complex which comprises the oligomer of  claim 75 , wherein
 L represents a bidentate ligand or   L=X 2 , where each X, independently, represents a monodentate ligand,   where L or at least one X contains a polymerizable group.   
   
   
       123 . The complex according to  claim 122 , wherein
 L or at least one X has a C═C group.   
   
   
       124 . The complex according to  claim 122 , wherein
 L represents   
     
       
         
         
             
             
         
       
       in which each R, independently, represents H, an alkyl, aryl, alkoxy, aryloxy, alkylamine or arylamine group. 
     
   
   
       125 . The complex according to  claim 116 ,
 wherein L 1 ∩L 2  is a linear or cyclic diene having 6 to 10 C atoms or a diphosphine selected from   
     
       
         
         
             
             
         
       
       
         
         
             
             
         
       
       where R represents alkyl, aryl, alkoxy, phenoxy, alkylamine or arylamine. 
     
   
   
       126 . The complex according to  claim 116 , wherein
 L 1 ∩L 2  represents Ph 2 P—CH 2 —CH 2 —PPh 2  or cyclooctadiene.   
   
   
       127 . The complex according to 116, which wherein the complex is (biphenyl)(cyclooctadiene)platinum, (bph)Pt(COD), or (biphenyl)(bis(diphenylphosphino)ethane)platinum, (bph)Pt(dppe) 
     
       
         
         
             
             
         
       
     
   
   
       128 . The complex according to  claim 116 , wherein in the complex is one complex selected from the following group