Abstract: A metal complex (1) is useful for producing a light emitting device having excellent external quantum efficiency. M represents Ir; n1 is 1 or more; n1+n2 is 3; E1 and E2 are nitrogen or carbon atoms; Ring L1 represents an aromatic hetero ring; Ring L2 represents an aromatic hydrocarbon or an aromatic hetero ring; A1-G1-A2 represents an anionic bidentate ligand, and Ring L1 or Ring L2 has a group (2). R3 represents an alkyl group; R4 to R8 are each a hydrogen atom or an alkyl group; X represents an arylene group; k1 represents 0 to 3. When (1) has only one type of (2), (i) is satisfied: (i) Ring L1 is a monocyclic 5-membered aromatic hetero ring; and at least one Ring L2 has formula (2) where R3 is a phenyl group, R4 is a hydrogen atom, and R3 and R4 are combined to form a fluorene ring.

Abstract: A composition contains metal complexes represented formulas (1) and (2): M1 and M2 represent an iridium atom; n1 and n3 represent an integer of 1 or more; n2 and n4 represent an integer of 0 or more; Ring R1A represents a triazole ring; Ring R2 represents an aromatic hydrocarbon ring; R11A to R13A are each hydrogen or a substituent; A1-G1-A2 represents an anionic bidentate ligand; at least one of E11A to E13A is a nitrogen atom, and at least one of R11A to R13A bonding to the nitrogen atom is a group represented by the formula (Ar-1A). Ring A represents an aromatic hydrocarbon ring and R2 represents a substituent. EL represents a carbon atom; Ring L1 represents a 6-membered aromatic hetero ring; Ring L2 represents an aromatic hydrocarbon ring; A3-G2-A4 represents an anionic bidentate ligand, and at least one of Ring L1 and Ring L2 has a substituent.

Abstract: A metal complex represented by formula (1) is provided. In formula (1), X represents a nitrogen atom or a group represented by ?C(RX)—; R1 represents an alkyl group having 4 or more carbon atoms; R2 represents an alkyl, cycloalkyl, alkoxy, cycloalkoxy, aryl, aryloxy, monovalent heterocyclic, or substituted amino group or a halogen atom; rings A and B each independently represent an aromatic hydrocarbon ring or an aromatic heterocyclic ring; M represents a rhodium, palladium, iridium, or platinum atom; n1 represents an integer of 1 or more, n2 represents an integer of 0 or more, and n1+n2 is 2 or 3; A1-G1-A2 represents an anionic bidentate ligand; A1 and A2 each independently represent a carbon atom, an oxygen atom, or a nitrogen atom; and G1 represents a single bond or an atomic group constituting a bidentate ligand together with A1 and A2.

Abstract: Provided is a polymer compound useful for production of a light emitting device excellent in external quantum yield. The polymer compound includes a constitutional unit represented by the formula (1): wherein a1 and a2 represent 0 or 1, ArA1 and ArA3 represent an arylene group or the like, and in each of ArA1 and ArA3 at least one atom adjacent to an atom forming a bond to the constitutional unit adjacent to the each of ArA1 and ArA3 has an alkyl group or the like as a substituent, ArA2 represents a phenylene group, ArA4 represents an arylene group or the like, RA1, RA2 and RA3 represent an aryl group or the like, and when a2 is 0, RA1 represents an aryl group in which two or more rings are condensed (the number of carbon atoms constituting the rings of the aryl group is 10 or more) or the like.

Abstract: A method for producing a 1,2,4-triazole compound involves reacting an amide compound represented by formula (2) with a hydrazide compound represented by formula (3) in a solvent in the presence of a Lewis acid and a Lewis base, thereby obtaining a 1,2,4-triazole compound represented by formula (1): R1 represents an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, an aryloxy group, a monovalent heterocyclic group or a substituted amino group, R2 and R3 each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group or a substituted amino group, and Ring A and Ring B each independently represent an aromatic hydrocarbon ring or an aromatic heterocyclic ring.

Abstract: A method for producing a 1,2,4-triazole compound involves reacting an amide compound represented by formula (2) with a hydrazide compound represented by formula (3) in a solvent in the presence of a Lewis acid and a Lewis base, thereby obtaining a 1,2,4-triazole compound represented by formula (1): R1 represents an alkyl group, a cycloalkyl group, an alkoxy group, a cycloalkoxy group, an aryl group, an aryloxy group, a monovalent heterocyclic group or a substituted amino group, R2 and R3 each independently represent a hydrogen atom, an alkyl group, a cycloalkyl group, an aryl group, a monovalent heterocyclic group or a substituted amino group, and Ring A and Ring B each independently represent an aromatic hydrocarbon ring or an aromatic heterocyclic ring.

Abstract: Provided is a polymer compound useful for production of a light emitting device excellent in external quantum yield. The polymer compound includes a constitutional unit represented by the formula (1): wherein a1 and a2 represent 0 or 1, ArA1 and ArA3 represent an arylene group or the like, and in each of ArA1 and ArA3 at least one atom adjacent to an atom forming a bond to the constitutional unit adjacent to the each of ArA1 and ArA3 has an alkyl group or the like as a substituent, ArA2 represents a phenylene group, ArA4 represents an arylene group or the like, RA1, RA2 and RA3 represent an aryl group or the like, and when a2 is 0, RA1 represents an aryl group in which two or more rings are condensed (the number of carbon atoms constituting the rings of the aryl group is 10 or more) or the like.