Organic electroluminescent element, and electronic apparatus

Abstract

An organic electroluminescence device includes an anode, an emitting layer, and a cathode. The emitting layer contains a delayed fluorescent first compound, a fluorescent second compound, and a third compound represented by Cz-Az. The second compound emits light with a main peak wavelength ranging from 430 nm to 540 nm. Az is a cyclic structure selected from the group consisting of a substituted or unsubstituted pyridine ring, a substituted or unsubstituted pyrimidine ring, a substituted or unsubstituted triazine ring, and a substituted or unsubstituted pyrazine ring. Cz is represented by a formula (3B) below.

1 . An organic electroluminescence device comprising:
 an anode;   an emitting layer; and   a cathode, wherein   the emitting layer comprises:   a delayed fluorescent first compound;   a fluorescent second compound; and   a third compound represented by a formula (3A):
   Cz-Az  (3A)
 
   the second compound emits light with a main peak wavelength ranging from 430 nm to 540 nm;   Az is a cyclic structure selected from the group consisting of a substituted or unsubstituted pyridine ring, a substituted or unsubstituted pyrimidine ring, a substituted or unsubstituted triazine ring, and a substituted or unsubstituted pyrazine ring;   Cz is represented by a formula (3B):   
       
         
           
           
               
               
           
         
         X 31  to X 38  are each independently a nitrogen atom or C-Rx; 
         Rx are each independently a hydrogen atom or a substituent selected from the group consisting of a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted fluoroalkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 30 ring carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, a substituted phosphoryl group, a substituted silyl group, a cyano group, a nitro group, and a carboxy group; 
         plural Rx are mutually the same or different; 
         when two or more of X 31  to X 38  are each C-Rx and Rx is a substituent, Rx are bonded together to form a ring or form no ring; and 
         * represents a bonding site to a carbon atom in the cyclic structure represented by Az. 
       
     
     
         2 . The organic electroluminescence device according to  claim 1 , wherein Cz in the formula (3A) is represented by a formula (a), a formula (b) or a formula (c): 
       
         
           
           
               
               
           
         
         X 31  to X 38  and X 41  to X 48  are each independently a nitrogen atom or C-Rx; 
         in the formula (a), at least one of X 35  to X 38  is a carbon atom bonded to one of X 41  to X 44  and at least one of X 41  to X 44  is a carbon atom bonded to one of X 35  to X 38 ; 
         in the formula (b), at least one of X 35  to X 38  is a carbon atom bonded to a nitrogen atom in a five-membered ring of a nitrogen-containing fused ring comprising X 41  to X 48 ; 
         in the formula (c), *a and *b each represent a bonding site to one of X 31  to X 38 , at least one of X 35  to X 38  is the bonding site represented by *a, at least one of X 35  to X 38  is the bonding site represented by *b, and n is an integer of 1 to 4; 
         R x  are each independently a hydrogen atom or a substituent selected from the group consisting of a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted fluoroalkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 30 ring carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, a substituted phosphoryl group, a substituted silyl group, a cyano group, a nitro group, and a carboxy group; 
         plural Rx are mutually the same or different; 
         when two or more of X 31  to X 38  are each C-Rx and Rx is a substituent, Rx are bonded together to form a ring or form no ring; 
         when two or more of X 41  to X 48  are each C-Rx and Rx is a substituent, Rx are bonded together to form a ring or form no ring; 
         Z 31  is one selected from the group consisting of an oxygen atom, a sulfur atom, NR 30 , and C(R 31 ) 2 ; 
         R 30  and R 31  are each independently a hydrogen atom or a substituent independently selected from the group consisting of a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted fluoroalkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 30 ring carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, a substituted phosphoryl group, a substituted silyl group, a cyano group, a nitro group, and a carboxy group; 
         plural R 30  are mutually the same or different; 
         plural R 31  are mutually the same or different; 
         when two or more of R 31  are each a substituent, R 31  are bonded together to form a ring or form no ring; and 
         * represents a bonding site to a carbon atom in the cyclic structure represented by Az. 
       
     
     
         3 . The organic electroluminescence device according to  claim 2 , wherein Cz in the formula (3A) is represented by a formula (a1), a formula (a2) or a formula (b1): 
       
         
           
           
               
               
           
         
         X 31  to X 38  and X 41  to X 48  are each independently a nitrogen atom or C-Rx; 
         R x  are each independently a hydrogen atom or a substituent selected from the group consisting of a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted fluoroalkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 30 ring carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, a substituted phosphoryl group, a substituted silyl group, a cyano group, a nitro group, and a carboxy group; 
         plural Rx are mutually the same or different; 
         when two or more of X 31  to X 38  are each C-Rx and Rx is a substituent, Rx are bonded together to form a ring or form no ring; 
         when two or more of X 41  to X 48  are each C-Rx and Rx is a substituent, Rx are bonded together to form a ring or form no ring; 
         Z 31  is one selected from the group consisting of an oxygen atom, a sulfur atom, NR 30 , and C(R 31 ) 2 ; 
         R 30  and R 31  are each independently a hydrogen atom or a substituent independently selected from the group consisting of a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted fluoroalkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 30 ring carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, a substituted phosphoryl group, a substituted silyl group, a cyano group, a nitro group, and a carboxy group; 
         plural R 30  are mutually the same or different; 
         plural R 31  are mutually the same or different; 
         when two or more of R 31  are each a substituent, R 31  are bonded together to form a ring or form no ring; and 
         * represents a bonding site to a carbon atom in the cyclic structure represented by Az. 
       
     
     
         4 . The organic electroluminescence device according to  claim 3 , wherein Z 31  is NR 30 . 
     
     
         5 . The organic electroluminescence device according to  claim 3 , wherein R 30  is a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms. 
     
     
         6 . The organic electroluminescence device according to  claim 2 , wherein X 41  to X 48  exclusive of one being the carbon atom bonded to the cyclic structure represented by the formula (3B) are each C-Rx. 
     
     
         7 . The organic electroluminescence device according to  claim 2 , wherein
 Cz in the formula (3A) is represented by the formula (c); and   n is 1.   
     
     
         8 . The organic electroluminescence device according to  claim 7 , wherein Cz in the formula (3A) is represented by a formula (c1): 
       
         
           
           
               
               
           
         
         X 31  to X 35 , X 38 , and X 41  to X 44  are each independently a nitrogen atom or C-Rx; 
         R x  are each independently a hydrogen atom or a substituent selected from the group consisting of a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted fluoroalkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 30 ring carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, a substituted phosphoryl group, a substituted silyl group, a cyano group, a nitro group, and a carboxy group; 
         plural Rx are mutually the same or different; 
         when two or more of X 31  to X 35  and X 38  are each C-Rx and Rx is a substituent, Rx are bonded together to form a ring or form no ring; 
         when two or more of X 41  to X 44  are each C-Rx and Rx is a substituent, Rx are bonded together to form a ring or form no ring; 
         Z 31  is one selected from the group consisting of an oxygen atom, a sulfur atom, NR 30 , and C(R 31 ) 2 ; 
         R 30  and R 31  are each independently a hydrogen atom or a substituent independently selected from the group consisting of a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted fluoroalkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 30 ring carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, a substituted phosphoryl group, a substituted silyl group, a cyano group, a nitro group, and a carboxy group; 
         plural R 30  are mutually the same or different; 
         plural R 31  are mutually the same or different; 
         when two or more of R 31  are each a substituent, R 31  are bonded together to form a ring or form no ring; and 
         * represents a bonding site to a carbon atom in the cyclic structure represented by Az. 
       
     
     
         9 . The organic electroluminescence device according to  claim 8 , wherein Z 31  in the formula (c1) is C(R 31 ) 2 . 
     
     
         10 . The organic electroluminescence device according to  claim 1 , wherein Az in the formula (3A) is a cyclic structure selected from the group consisting of a substituted or unsubstituted pyrimidine ring and a substituted or unsubstituted triazine ring. 
     
     
         11 . The organic electroluminescence device according to  claim 1 , wherein
 Az in the formula (3A) is a cyclic structure selected from the group consisting of a substituted pyrimidine ring and a substituted triazine ring; and   a substituent for the pyrimidine ring and the triazine ring is a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms and a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms.   
     
     
         12 . The organic electroluminescence device according to  claim 1 , wherein when Az comprises a substituted or unsubstituted aryl group as a substituent, the substituent is selected from the group consisting of a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted phenanthryl group, a substituted or unsubstituted terphenyl group, and a substituted or unsubstituted fluorenyl group. 
     
     
         13 . The organic electroluminescence device according to  claim 1 , wherein when Az comprises a substituted or unsubstituted aryl group as a substituent, the substituent is selected from the group consisting of a substituted or unsubstituted phenyl group, a substituted or unsubstituted biphenyl group, and a substituted or unsubstituted naphthyl group. 
     
     
         14 . The organic electroluminescence device according to  claim 1 , wherein when Az comprises a substituted or unsubstituted heteroaryl group as a substituent, the substituent is selected from the group consisting of a substituted or unsubstituted carbazolyl group, a substituted or unsubstituted dibenzofuranyl group, and a substituted or unsubstituted dibenzothienyl group. 
     
     
         15 . The organic electroluminescence device according to  claim 1 , wherein X 31  to X 38  are each C-Rx. 
     
     
         16 . The organic electroluminescence device according to  claim 1 , wherein Rx are each independently a hydrogen atom or a substituent selected from the group consisting of a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms and a substituted or unsubstituted heteroaryl group having 5 to 30 ring atoms. 
     
     
         17 . The organic electroluminescence device according to  claim 1 , wherein the second compound emits light with a main peak wavelength ranging from 430 nm to 480 nm. 
     
     
         18 . The organic electroluminescence device according to  claim 1 , further comprising a hole transporting layer between the anode and the emitting layer. 
     
     
         19 . The organic electroluminescence device according to  claim 1 , further comprising an electron transporting layer between the cathode and the emitting layer. 
     
     
         20 . An electronic device comprising the organic electroluminescence device according to  claim 1 .