Indenofluorenedione derivative, material for organic electroluminescent element, and organic electroluminescent element

Abstract

An indenofluorenedione derivative having a specific structure, which is useful as a material for organic electroluminescence devices because the derivative is excellent in heat resistance and can be vapor-deposited on a substrate at moderate temperature. An organic electroluminescence device including an anode, a cathode, and an organic thin layer between the anode and the cathode, which contains the material for organic electroluminescence devices in the organic thin layer, is driven at a low driving voltage and has a long lifetime.

1 . An indenofluorenedione derivative represented by formula (I): 
       
         
           
           
               
               
           
         
         wherein
 Ar 1  is a condensed ring having 6 to 24 nuclear carbon atoms or a heteroring having 6 to 24 nuclear atoms, 
 ar 1  and ar 2  may be the same or different and each independently represent a structure represented by formula (i) or (ii): 
 
       
       
         
           
           
               
               
           
         
         wherein X 1  and X 2  may be the same or different and selected from the following divalent groups represented by formulae (a) to (g): 
       
       
         
           
           
               
               
           
         
         wherein R 21  to R 24  may be the same or different and each independently represent a hydrogen atom, a substituted or unsubstituted fluoroalkyl group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group, and R 22  and R 23  may bond to each other to form a ring,
 R 1  to R 4  may be the same or different and each independently represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, a substituted or unsubstituted alkenyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a halogen atom, a substituted or unsubstituted fluoroalkyl group, a substituted or unsubstituted alkoxyl group, a substituted or unsubstituted fluoroalkoxyl group, a substituted or unsubstituted aryloxy group, a substituted or unsubstituted aralkyloxy group, a substituted or unsubstituted amino group, or cyano group, and R 1  and R 2 , and R 3  and R 4  may bond to each other to form a saturated or unsaturated divalent group completing a ring, and 
 Y 1  and Y 4  may be the same or different and each represent —N═, —CH═, or —C(R 5 )═, wherein R 5  is defined in the same manner as in R 1  to R 4 , and adjacent groups of R 1  to R 5  may bond to each other to form a saturated or unsaturated divalent group completing a ring, 
 wherein the indenofluorenedione derivative represented by formula (I) does not include a compound represented by formula (iii), (iv), or (v): 
 
       
       
         
           
           
               
               
           
         
         wherein X 1  and X 2  are defined in the same manner as in formula (I); R 1  to R 4  and R 8  to R 17  are defined in the same manner as in R 1  to R 4  of formula (I), and Y 5  to Y 14  are defined in the same manner as in Y 1  to Y 4  of formula (I). 
       
     
     
         2 . The indenofluorenedione derivative according to  claim 1 , which is represented by any one of formulae (II) to (VII): 
       
         
           
           
               
               
           
         
         wherein X 1 , X 2 , and R 1  to R 4  are defined in the same manner as in formula (I) and Y 21  to Y 26  and Y 31  to Y 38  are defined in the same manner as in Y 1  to Y 4  of formula (I). 
       
     
     
         3 . The indenofluorenedione derivative according to  claim 1 , wherein at least one of Y 1  to Y 4 , Y 21  to Y 26 , and Y 31  to Y 38  of formulae (I) to (VII) is a nitrogen atom. 
     
     
         4 . The indenofluorenedione derivative according to  claim 1 , wherein at least one of R 1  to R 4  of formulae (I) to (VII) is selected from the group consisting of a fluorine atom, a fluoroalkyl group, a fluoroalkoxyl group, a cyano group, an aryl group and a heterocyclic group each having at least one substituent selected from the group consisting of fluorine, a fluoroalkyl group, a fluoroalkoxyl group, and a cyano group. 
     
     
         5 . A material for organic electroluminescence devices comprising the indenofluorenedione derivative as defined in  claim 1 . 
     
     
         6 . The material for organic electroluminescence devices according to  claim 5 , which has a reduction potential of −1.0 V vs. Fc + /Fc, wherein Fc is ferrocene, when measured in an acetonitrile solution. 
     
     
         7 . The material for organic electroluminescence devices according to  claim 5 , which is a hole injecting material. 
     
     
         8 . An organic electroluminescence device comprising an anode, a cathode, and an organic thin layer between the anode and the cathode, wherein the organic thin layer comprises the material for organic electroluminescence devices as defined in  claim 5 . 
     
     
         9 . The organic electroluminescence device according to  claim 8 , wherein the organic thin layer is a laminate comprising a hole injecting layer, a hole transporting layer, a light emitting layer, and an electron transporting layer in that order from a side of the anode.