Metal complex compound and organic electroluminescent element using the same

Abstract

The present invention provides a novel metal complex compound represented by the following general formula (1), and an organic electroluminescence element which has a high efficiency of light emission and a long lifetime, wherein one of organic thin film layers including at least a light emitting layer between an anode and a cathode, a least one of the organic thin film layers contains the metal complex compounds. (L 1 ) m M(L 2 ) n   (1) wherein M represents Ir, Pt and Rh; L 1 and L 2 represents mutually different bidentate ligands; (L 1 ) m M as a partial structure is represented by general formula (2) and M(L 2 ) n as a partial structure is represented by general formula (3): and m and n are each an integer of 1 or 2, provided that m+n is a integer of 2 or 3. wherein ring A1 represents an aromatic, hetrocyclic ring group: and ring B1 represents an aryl group, provided that the ring A1 and the ring B1 are covalently linked to each other via Z which represents a single bond or the like. wherein R 1 , R 2 , R 2 ′ and R 3 each independently represent an alkyl group or the like; R 1 and R 2 , R 1 and R 2 ′, R 2 and R 2 ′. R 2 and R 3 , and R 2 ′ and R 3 may combine with each other to form a cyclic structure; and Y represents a group represented by O or S.

1 . A metal complex compound represented by the following general formula (1):
   (L 1 ) m M(L 2 ) n    (1)   wherein M represents a metal atom selected from the group consisting of iridium (Ir), platinum (Pt) and rhodium (Rh), L 1  and L 2  represent bidentate ligands which are different from each other, the sectional structure (L 1 ) m M is represented by the following general formula (2), the sectional structure M(L 2 ) a  is represented by the following general formula (3), and m and n each represents an integer of 1 or 2, and m+n represents an integer of 2 or 3;   
       
         
           
           
               
               
           
         
         wherein N and C each represents a nitrogen atom and a carbon atom, A1 ring represents a substituted or unsubstituted aromatic heterocyclic group having 3 to 50 ring carbon atoms which may contain a nitrogen atom, and B1 ring represents a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, and the A1 ring and the B1 ring is linked each other by a covalent bond via Z; 
         wherein Z represents a single bond, —O—, —S—, —CO—, —(CR′R″) a —, —(SiR′R″) a — or —NR′—, in which R′ and R″ each independently represents a hydrogen atom, a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, a substituted or unsubstituted aromatic heterocyclic group having 3 to 50 ring atoms, or a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a represents an integer of 1 to 10, and R′ and R″ are the same with or different from each other; 
       
       
         
           
           
               
               
           
         
         wherein N represents a nitrogen atom, and R 1 , R 2 , R 2 ′ and R 3  each independently represents a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 50 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 50 ring carbon atoms, R 2 ′ may be a hydrogen atom, R 1  and R 2 , R 1  and R 2 ′, R 2 , and R 2 ′ R 2 , and R 3 , and R 2 ′ and R 3  may be inked each other to form a saturated or unsaturated ring structure, and Y represents a group represented by an oxygen atom or a sulfur atom; 
         with the proiso that the metal complex compound is not one represented by the following general formula (4) and (8) 
       
       
         
           
           
               
               
           
         
         wherein M and m are as defined in formula (1), R 4  to R 11  each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted halogenated alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted heterocyclic group having 3 to 20 ring atoms, a substituted or unsubstituted aryl group having 6 to 40 ring carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 40 ring carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 40 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted arylamino group having 6 to 80 ring carbon atoms, a substituted or unsubstituted alkylamino group having 1 to 60 carbon atoms, a substituted or unsubstituted aralkylamino group having 7 to 80 carbon atoms, a substituted or unsubstituted alkylsilyl group having 1 to 30 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 40 carbon atoms, a halogen atom, a cyano group, a nitro group, —S(R)O 2 , or —S(R)O; wherein R represents a substituent, and neighboring groups among R 4  to R 11  may be linked to each other to form a saturated or unsaturated ring structure; 
       
       
         
           
           
               
               
           
         
         wherein M and n are as defined in formula (1), R 31  to R 34  each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted halogenated alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted heterocyclic group having 3 to 20 ring atoms, a substituted or unsubstituted aryl group having 6 to 40 ring carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 40 ring carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 40 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted arylamino group having 6 to 80 ring carbon atoms, a substituted or unsubstituted alkylamino group having 1 to 60 carbon atoms, a substituted or unsubstituted aralkylamino group having 7 to 80 carbon atoms, a substituted or unsubstituted alkylsilyl group having 1 to 30 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 40 carbon atoms, a halogen atom, a cyano group, a nitro group, —S(R)O 2 , or —S(R)O, wherein R represents a substituent, and neighboring groups among R 31  and R 32 , R 32  and R 33 , and R 33  and R 34  may be linked to each other to form a saturated or unsaturated ring structure. 
       
     
     
         2 . The metal complex compound according to  claim 1 , wherein the sectional structure M(L 2 ) n  of the above general formula (1) is represented by the following general formula (3′): 
       
         
           
           
               
               
           
         
         wherein N represents a nitrogen atom, M, Y, R 1 , R 2  and R 3  are the same with the aforementioned, R 1  and R 2 , and R 2  and R 3  may be inked each other to form a saturated or unsaturated ring structure. 
       
     
     
         3 . The metal complex compound according to  claim 1 , wherein the sectional structure (L 1 ) m M of the general formula (2) is a metal complex compound represented by the general formula (4), (5) or (6): 
       
         
           
           
               
               
           
         
         wherein M and m are the same with the aforementioned, R 4  to R 26  each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted halogenated alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted heterocyclic group having 3 to 20 ring atoms, a substituted or unsubstituted aryl group having 6 to 40 ring carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 40 ring carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 40 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted arylamino group having 6 to 80 ring carbon atoms, a substituted or unsubstituted alkylamino group having 1 to 60 carbon atoms, a substituted or unsubstituted aralkylamino group having 7 to 80 carbon atoms, a substituted or unsubstituted alkylsilyl group having 1 to 30 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 40 carbon atoms, a halogen atom, a cyano group, a nitro group, —S(R)O 2 , or —S(R)O; wherein R represents a substituent, and neighboring groups among R 4  to R 11 , R 12  to R 19  and R 20  to R 26  may be inked each other to form a saturated or unsaturated ring structure. 
       
     
     
         4 . The metal complex compound according to  claim 1 , wherein the sectional structure M(L 2 ) n  of the general formula (3) is a metal complex compound represented by the following general formula (7): 
       
         
           
           
               
               
           
         
         wherein M, Y and n are the same with aforementioned, R 27  to R 30  each independently represents the same with R 4  to R 26  of the aforementioned general formulae (4) to (6), and R 27  and R 28 , R 28  and R 29 , and R 29  and R 30  may be linked each other to form a saturated or unsaturated ring structure. 
       
     
     
         5 . The metal complex compound according to  claim 1 , wherein the sectional structure (L 1 ) m M of the above general formula (2) is a sectional structure represented by the following general formula (4), (5) or (6), and the sectional structure M(L 2 ) n  of the above general formula (3) is a sectional structure represented by the above general formula (7): 
       
         
           
           
               
               
           
         
         wherein M and m are the same with the afore mentioned, R 4  to R 26  each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted halogenated alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted heterocyclic group having 3 to 20 ring atoms, a substituted or unsubstituted aryl group having 6 to 40 ring carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 40 ring carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 40 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted arylamino group having 6 to 80 ring carbon atoms, a substituted or unsubstituted alkylamino group having 1 to 60 carbon atoms, a substituted or unsubstituted aralkylamino group having 7 to 80 carbon atoms, a substituted or unsubstituted alkylsilyl group having 1 to 30 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 40 carbon atoms, a halogen atom, a cyano group, a nitro group, —S(R)O 2 , or —S(R)O, wherein R represents a substituent, and neighboring groups among R 4  to R 11 , R 12  to R 19  and R 20  to R 26  may be linked each other to form a saturated or unsaturated ring structure; 
       
       
         
           
           
               
               
           
         
         wherein M, Y and n are the same with aforementioned, R 27  to R 30  each independently represents the same with R 4  to R 26  of the aforementioned general formulae (4) to (6), and R 27  and R 28 , R 28  and R 29 , and R 22  and R 30  may be linked each other to form a saturated or unsaturated ring structure. 
       
     
     
         6 . The metal complex compound according to  claim 1 , wherein the sectional structure (L 1 ) m M of the above general formula (2) is a sectional structure represented by the following general formula (5) or (6), and the sectional structure M(L 2 ) n  of the above general formula (3) is a sectional structure represented by the following general formula (8): 
       
         
           
           
               
               
           
         
         wherein M and m are the same with the aforementioned, R 4  to R 26  each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted halogenated alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted heterocyclic group having 3 to 20 ring atoms, a substituted or unsubstituted aryl group having 6 to 40 ring carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 40 ring carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 40 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 30 carbon atoms, a substituted or unsubstituted arylamino group having 6 to 80 ring carbon atoms, a substituted or unsubstituted alkylamino group having 1 to 60 carbon atoms, a substituted or unsubstituted aralkylamino group having 7 to 80 carbon atoms, a substituted or unsubstituted alkylsilyl group having 1 to 30 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 40 carbon atoms, a halogen atom a cyano group a vitro group; —S(R)O 2 , or —S(R)O, wherein R represents a substituent, and neighboring groups among R 4  to R 11 , R 12  to R 19  and R 20  to R 26  may be inked each other to form a saturated or unsaturated ring structure; 
       
       
         
           
           
               
               
           
         
         wherein R 31  to R 34  each independently is the same with R 27  to R 30  of the above general formula (7). 
       
     
     
         7 . An organic electroluminescence device comprising at least any one of organic thin layers including a light emitting layer between an anode and a cathode, wherein at least any one of the organic thin film layers contains a metal complex compound of  claim 1 . 
     
     
         8 . The organic electroluminescence device according to  claim 7 , wherein said light emitting layer contains the metal complex compound as a light emitting material. 
     
     
         9 . The organic electroluminescence device according to  claim 7 , wherein said light emitting layer contains the metal complex compound as a dopant. 
     
     
         10 . The organic electroluminescence device according to  claim 7 , wherein the device comprises at least any one of an electron injecting layer and an electron transporting layer between said light emitting layer and the cathode, and at least any one of the electron injecting layer and the electron transporting layer contains a π-electron deficiency nitrogen-containing heterocyclic derivative as the main component. 
     
     
         11 . The organic electroluminescence device according to  claim 7 , wherein a reductive dopant is added in an interface area between the cathode and said organic thin film layer.