Dibenzo[f,h]Quinoxaline Derivative, Method of Synthesizing the Same, Light-Emitting Element, Light-Emitting Device, Electronic Appliance, and Lighting Device

Abstract

A dibenzo[f,h]quinoxaline derivative in which impurities are reduced and a novel method of synthesizing the dibenzo[f,h]quinoxaline derivative in which impurities are reduced are provided. In addition, a light-emitting element, a light-emitting device, an electronic appliance, or a lighting device with high emission efficiency and high reliability in which the dibenzo[f,h]quinoxaline derivative is used as an EL material is provided. In the synthesis method, a 2-(chloroaryl)dibenzo[f,h]quinoxaline derivative is used as a synthetic intermediate in a synthetic pathway so that an impurity contained in a final product can be removed easily by purification by sublimation.

What is claimed is: 
     
         1 . A light-emitting element comprising:
 a pair of electrodes; and   an EL layer between the pair of electrodes,   wherein the EL layer contains a dibenzo[f,h]quinoxaline derivative,   wherein the dibenzo[f,h]quinoxaline derivative includes hydrogen at a 3-position and an aryl group at a 2-position of a dibenzo[f,h]quinoxaline skeleton,   wherein the aryl group includes at least one aryl group or heteroaryl group as a substituent, and   wherein the dibenzo[f,h]quinoxaline derivative contains 10 ppm or less of chlorine.   
     
     
         2 . A light-emitting element comprising:
 a pair of electrodes; and   an EL layer between the pair of electrodes,   wherein the EL layer contains a light-emitting layer,   wherein the light-emitting layer contains a dibenzo[f,h]quinoxaline derivative,   wherein the dibenzo[f,h]quinoxaline derivative includes hydrogen at a 3-position and an aryl group at a 2-position of a dibenzo[f,h]quinoxaline skeleton,   wherein the aryl group includes at least one aryl group or heteroaryl group as a substituent, and   wherein the light-emitting layer contains 10 ppm or less of chlorine.   
     
     
         3 . A light-emitting element comprising:
 a pair of electrodes; and   an EL layer between the pair of electrodes,   wherein the EL layer contains a light-emitting layer,   wherein the light-emitting layer contains a dibenzo[f,h]quinoxaline derivative,   wherein the dibenzo[f,h]quinoxaline derivative includes hydrogen at a 3-position and an aryl group at a 2-position of a dibenzo[f,h]quinoxaline skeleton,   wherein the aryl group includes at least one aryl group or heteroaryl group as a substituent, and   wherein the dibenzo[f,h]quinoxaline derivative contains 10 ppm or less of chlorine.   
     
     
         4 . The light-emitting element according to  claim 1 ,
 wherein the dibenzo[f,h]quinozaline derivative represented by General Formula (G1),   
       
         
           
           
               
               
           
         
         wherein Ar 1  represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, Ar 2  represents a substituted or unsubstituted aryl group having 6 to 40 carbon atoms or a substituted or unsubstituted heteroaryl group having 6 to 40 carbon atoms, R 1  to R 8  separately represent hydrogen, an alkyl group having 1 to 6 carbon atoms, a phenyl group, or a phenyl group having an alkyl group having 1 to 6 carbon atoms as a substituent, and n is any of 1 to 3. 
       
     
     
         5 . The light-emitting element according to  claim 2 ,
 wherein the dibenzo[f,h]quinozaline derivative represented by General Formula (G1),   
       
         
           
           
               
               
           
         
         wherein Ar 1  represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, Ar 2  represents a substituted or unsubstituted aryl group having 6 to 40 carbon atoms or a substituted or unsubstituted heteroaryl group having 6 to 40 carbon atoms, R 1  to R 8  separately represent hydrogen, an alkyl group having 1 to 6 carbon atoms, a phenyl group, or a phenyl group having an alkyl group having 1 to 6 carbon atoms as a substituent, and n is any of 1 to 3. 
       
     
     
         6 . The light-emitting element according to  claim 3 ,
 wherein the dibenzo[f,h]quinozaline derivative represented by General Formula (G1),   
       
         
           
           
               
               
           
         
         wherein Ar 1  represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms, Ar 2  represents a substituted or unsubstituted aryl group having 6 to 40 carbon atoms or a substituted or unsubstituted heteroaryl group having 6 to 40 carbon atoms, R 1  to R 8  separately represent hydrogen, an alkyl group having 1 to 6 carbon atoms, a phenyl group, or a phenyl group having an alkyl group having 1 to 6 carbon atoms as a substituent, and n is any of 1 to 3. 
       
     
     
         7 . The light-emitting element according to  claim 4 ,
 wherein the heteroaryl group contains one of a carbazole skeleton, a dibenzothiophene skeleton and a dibenzofuran skeleton.   
     
     
         8 . The light-emitting element according to  claim 5 ,
 wherein the heteroaryl group contains one of a carbazole skeleton, a dibenzothiophene skeleton and a dibenzofuran skeleton.   
     
     
         9 . The light-emitting element according to  claim 6 ,
 wherein the heteroaryl group contains one of a carbazole skeleton, a dibenzothiophene skeleton and a dibenzofuran skeleton.   
     
     
         10 . The light-emitting element according to  claim 1 ,
 wherein the dibenzo[f,h]quinozaline derivative represented by Formula (200).   
       
         
           
           
               
               
           
         
       
     
     
         11 . The light-emitting element according to  claim 2 ,
 wherein the dibenzo[f,h]quinozaline derivative represented by Formula (200).   
       
         
           
           
               
               
           
         
       
     
     
         12 . The light-emitting element according to  claim 3 ,
 wherein the dibenzo[f,h]quinozaline derivative represented by Formula (200).   
       
         
           
           
               
               
           
         
       
     
     
         13 . The light-emitting element according to  claim 1 ,
 wherein the light-emitting element keeps 90% or more of an initial luminance after 200 hours under a current with a density of 10 mA/cm 2 .   
     
     
         14 . The light-emitting element according to  claim 2 ,
 wherein the light-emitting element keeps 90% or more of an initial luminance after 200 hours under a current with a density of 10 mA/cm 2 .   
     
     
         15 . The light-emitting element according to  claim 3 ,
 wherein the light-emitting element keeps 90% or more of an initial luminance after 200 hours under a current with a density of 10 mA/cm 2 .