Patent ID: 9520574
Filing Date: 2016-12-13
CPC Classification: C07F,C09K,H01L,H05B

Claim Text:
1. An organic electroluminescent device comprising: a pair of electrodes comprising an anode and a cathode, and one or more layers of organic compound arranged between the anode and the cathode, wherein at least one of the one or more layers of organic compound comprises a phosphorescent material; wherein the phosphorescent material comprises a complex of a metal atom M selected from Ir, Pt, Rh, Pd, Ru and Os and at least one ligand L, wherein the ligand L is represented by formula (1): wherein: ring A is a substituted or unsubstituted 5-membered heterocycle containing at least one ring nitrogen atom bound to the metal atom at the asterisk (*), wherein ring A may be substituted with one or more substituents selected from the group consisting of: ring B is a substituted or unsubstituted 5- or 6-membered carbocycle or heterocycle containing a carbon atom as represented in formula (1) which is bound to the metal atom at the asterisk (*), rings A and B are joined by a direct covalent bond as represented in formula (1), rings A and B are joined via a tether Q, wherein Q is a tether of between 3 and 20 atoms in length, and is selected from the group consisting of: linear, branched or cyclic alkyl; linear or branched alkenyl; linear or branched alkynyl; aryl; and alkyl-aryl; wherein one or more of the carbon atoms in the alkyl, aryl or alkyl-aryl may be replaced, wherein each carbon atom that is replaced is independently replaced with an atom or group selected from the group consisting of: —C(═O)—, —O—, —S—, —N—, ═N—, —Si— and —P—; wherein when the atom is ═N—, the nitrogen double bond is to an adjacent carbon atom in the alkyl, aryl, or alkyl-aryl so as to form a —C═N— group; and wherein the tether may contain one or more substituents selected from the group consisting of halogen, cyano, amide, imine, imide, amidine, amine, nitro, hydroxy, ether, carbonyl, carboxy, carbonate, carbamate, phosphine, phosphate, phosphonate, sulphide, sulphone, sulphoxide, alkenyl, aryl, alkyl, heteroaryl, alkynyl, silyl, and substituents containing a functional group that can be polymerised, a polymer chain, or two substituents may together form a ring or fused ring system.