The present disclosure relates in parts to compounds capable of emitting delayed fluorescence and uses of these compounds in organic light-emitting diodes.

A compound having a structure of ##STR00001##
is disclosed. In these formulas, each R.sub.1, R.sub.2, and R.sub.3 is independently selected from hydrogen, alkyl, and aryl; at least one of R.sub.1 and R.sub.2 is a branched alkyl containing at least 4 carbon atoms, where the branching occurs at a position further than the benzylic position; where R.sub.1 and R.sub.3 are mono-, di-, tri-, tetra-, or no substitutions; and R.sub.2 is mono-, di-, or no substitutions. Heteroleptic iridium complexes including such compounds, and devices including such compounds are also disclosed.

Disclosed herein are compounds capable of producing organic electroluminescence (EL) devices having excellent properties, organic EL devices comprising the compounds, and electronic devices comprising the organic EL devices. The compounds of this disclosure are represented by formula (1) below, where A, B, C, and R.sub.1 to R.sub.11 are defined herein. ##STR00001##

The present disclosure relates to a plurality of host materials comprising a first host material having a compound represented by formula 1, and a second host material having a compound represented by formula 2, and an organic electroluminescent device comprising the same. By comprising a specific combination of compounds of the present disclosure as host materials, it is possible to provide an organic electroluminescent device having long lifetime properties while having an equivalent or improved level of power efficiency compared to conventional organic electroluminescent devices.

A compound comprising a first ligand L.sub.A of Formula I,

##STR00001##

is provided. In Formula I, moiety A is a heterocyclic fused ring system comprising a 5-membered ring fused to a 6-membered ring; moiety B is an aromatic ring or fused ring system; each R.sup.A and R.sup.B is independently a hydrogen or a General Substituent; K is a direct bond, O, or S; at least one of R.sup.A and R.sup.B comprises a substituent R comprising a silyl group or a germyl group; ligand L.sub.A is coordinated to a metal M, which has an atomic mass of at least 40; and metal M may be coordinated to other ligands Formulations, OLEDs, and consumer products containing the same are also provided.

The present disclosure relates in part to compounds capable of emitting delayed fluorescence and uses of these compounds in organic light-emitting diodes.

According to an aspect of the present disclosure, a compound having a metal planar tetradentate coordination configuration is disclosed. In the compounds, the metal M is Pt or Pd; the four coordinating atoms are Z.sup.1, Z.sup.2, Z.sup.3, and Z.sup.4 and are each selected from N, C, and O. The compound includes a substituent R, and atoms M, Z.sup.1, Z.sup.2, Z.sup.3, and Z.sup.4 are used to define a first plane that passes through the metal M and is positioned to have a minimum sum of shortest distances with Z.sup.1, Z.sup.2, Z.sup.3, and Z.sup.4. At least one non-hydrogen atom in R falls within a distal circle of a cylinder extending perpendicular to the first plane, where the distal circle of the cylinder is a height h from the base circle and the height h ranges from 3.3 Å to 4.8 Å.

A compound including a first ligand L.sub.A of Formula I,

##STR00001##

is provided. In Formula I, each of moiety A and moiety B independently represents monocyclic or polycyclic rings; one of Z.sup.1 and Z.sup.2 is C and the other is N; K is a direct bond, O, or S; at least one R.sup.A or R.sup.B has a structure of Formula II,

##STR00002##

where at least two of X.sup.1 to X.sup.4 are C; L is a direct bond or an organic linker; each R, R′, R″, R.sup.A, R.sup.B, and R.sup.C is a hydrogen or a General Substituent; and L.sub.A is coordinated to a metal M. Formulations, OLEDs, and consumer products containing the compound are also provided.

Heteroleptic compounds having a structure of Ir(L.sub.A).sub.p(L.sub.B).sub.q(L.sub.C).sub.r, where L.sub.B and L.sub.C are different bidentate ligands, p is 1 or 2, q is 1 or 2, r is 0, 1, or 2, and ligand L.sub.A has a structure of Formula I,

##STR00001##

In Formula I, moiety B is a monocyclic or polycyclic fused ring system; each of X.sup.1 to X.sup.6 is C or N; each R.sup.A, R.sup.B, and R.sup.C is independently a hydrogen or a general substituent; at least one R.sup.B comprises a partially or fully deuterated alkyl or cycloalkyl group; if moiety B is phenyl, at least two adjacent R.sup.C substituents are fused to form a ring, with the proviso that at least one L.sup.B or L.sup.C is present and is not a phenylpyridine-based ligand. Formulations, OLEDs, and consumer products containing the same are also disclosed.

A compound of Formula Ir(L.sub.A).sub.x(L.sub.B).sub.y(L.sub.C).sub.z is provided. Ligand L.sub.A has a structure of Formula I,

##STR00001##

ligand L.sub.B has a structure of Formula II,

##STR00002##

ligand L.sub.C is a bidentate ligand; at least one of R.sup.A and R.sup.B comprises Formula III,

##STR00003##

and L.sub.A, L.sub.B, and L.sub.C are different. In Formulae I and II, each of moiety A, B, C, and D is a ring or a fused-ring system; each of Z.sup.1 to Z.sup.8 and X.sup.1 to X.sup.5 is C or N; K is a direct bond, O, or S; L is a direct bond or a linker; and Q is Si or Ge. Formulations, OLEDs, and consumer products containing the compound are also provided.