Provided are compounds comprising a first ligand L.sub.A; wherein L.sub.A comprises a 5-membered heterocycle joined to a metal M by a M-C or M-N bond; wherein the 5-membered heterocycle comprises at least one boron atom; wherein M is selected from the group consisting of Os, Ir, Pd, Pt, Cu, Ag, and Au; and wherein L.sub.A does not comprise a structure of Formula I.

##STR00001##

wherein X is B or N; with the proviso that the 5-membered heterocycle does not comprise a B—B bond; and with the proviso that if M is Pd or Pt and the 5-membered heterocycle is fused to a benzene ring, the benzene ring is not part of a 6-membered chelate ring comprising M. Also provided are formulations comprising these compounds. Further provided are OLEDs and related consumer products that utilize these compounds.

An organic electroluminescence device includes an anode, an emitting layer, and a cathode in this order. The emitting layer comprises a delayed fluorescent compound M2 and a compound M3 having at least one deuterium atom, and the compound M3 is not a compound having a partial structure represented by a formula (1C) or (2C). S.sub.1(M2) of the compound M2 and S.sub.1(M3) of the compound M3 satisfy a relationship of S.sub.1(M3)>S.sub.1(M2). In the formulae (1C) and (2C), Y.sub.41 to Y.sub.48 are each independently a N atom, CR, or a C atom bonded to another atom or the like in the compound M3, where each R is independently a H atom or a substituent, at least one of Y.sub.41 to Y.sub.48 is a N atom, and at least one of Y.sub.41 to Y.sub.48 is a C atom bonded to another atom or the like in the compound M3.

##STR00001##

A compound is represented by a formula (1). n is 2 to 4, m is 1 to 4, q is 0 to 3, and m+n+q=6; CN is a cyano group; D.sub.1 is a group represented by a formula (2), (3) or (3X), the plurality of D.sub.1 are the same; and Rx is a hydrogen atom or substituent. R.sub.1 to R.sub.8 are each independently a hydrogen atom or substituent. R.sub.31 to R.sub.38 and R.sub.41 to R.sub.48 are each independently a hydrogen atom or substituent; p, px and py are each independently 1 to 4; A to C are each independently a cyclic structure represented by a formula (131) or (132). R.sub.19 and R.sub.20 are each independently a hydrogen atom or substituent. X.sub.1 is a sulfur atom or the like, and * represents a bonding position with a carbon atom of a benzene ring in the formula (1).

##STR00001##

A thermally activated, sensitized phosphorescence organic electroluminescence device includes a luminescent layer formed of a host material consisting of two materials, one being a hole transport material, and the other an electron transport material, at least one which is a thermally activated delayed fluorescence material. The host material is doped by a phosphorescent dye. The triplet state energy level of the CT excited state of the fluorescence material is higher than the triplet state energy level of the n-π excited state by 0 to 0.3 or the triplet state energy level of the CT excited state of the fluorescence material is higher than the triplet state energy level of the n-π excited state, wherein the difference is above 1.0 eV, and, a difference between the second triplet state energy level of its n-π excited state and the first singlet state energy level of its CT excited state is −0.1 to 0.1 eV.

The present invention relates to a compound of the formula (1), to the use of the compound in an electronic device, and to an electronic device comprising a compound of the formula (1). The present invention furthermore relates to a formulation comprising one or more compounds of the formula (1).

An organic electroluminescence device includes: an anode; an emitting layer; and a cathode, the emitting layer containing a first material, a second material and a third material, the first material being a fluorescent material, the second material being a delayed fluorescent material, the third material having a singlet energy larger than a singlet energy of the second material.

An organic light-emitting device includes: a first electrode; a second electrode facing the first electrode; and an organic layer between the first electrode and the second electrode, the organic layer including an emission layer. The emission layer includes at least one organometallic compound of Formula 1, and at least one selected from a second compound and a third compound, where the organometallic compound, the second compound, and the third compound are different from each other. When the emission layer comprises both the second compound and the third compound, the second compound and the third compound form an exciplex, and the organometallic compound and the second compound and/or the third compound do not form an exciplex:
M(L.sub.1).sub.n1(L.sub.2).sub.n2,  Formula 1
wherein in Formula 1, L.sub.1 is represented by Formula 2-1: ##STR00001##

Embodiments provide a novel condensed cyclic compound, a light-emitting device including the condensed cyclic compound, and an electronic apparatus including the light-emitting device. The light-emitting device includes a first electrode, a second electrode facing the first electrode, and an interlayer between the first electrode and the second electrode, wherein the interlayer includes an emission layer, and at least one of the condensed cyclic compound. The condensed cyclic compound is represented by Formula 1, which is explained in the specification:

##STR00001##

Provided is a light-emitting element with high emission efficiency including a fluorescent material as a light-emitting substance. In a light-emitting element including a pair of electrodes and an EL layer between the pair of electrodes, a delayed fluorescence component due to triplet-triplet annihilation accounts for 20% or more of light emitted from the EL layer, and the light has at least one emission spectrum peak in the blue wavelength range. The EL layer includes an organic compound in which an energy difference between the lowest singlet excited energy level and the lowest triplet excited energy level is 0.5 eV or more. The EL layer includes a benzo[a]anthracene compound.

Provided is a light-emitting element with high emission efficiency including a fluorescent material as a light-emitting substance. In a light-emitting element including a pair of electrodes and an EL layer between the pair of electrodes, a delayed fluorescence component due to triplet-triplet annihilation accounts for 20% or more of light emitted from the EL layer, and the light has at least one emission spectrum peak in the blue wavelength range. The EL layer includes an organic compound in which an energy difference between the lowest singlet excited energy level and the lowest triplet excited energy level is 0.5 eV or more. The EL layer includes a benzo[a]anthracene compound.