Transition metal complexes with carbene ligands as emitters for organic light-emitting diodes (OLEDs)

摘要

Use of transition metal complexes of the formula (I) in organic light-emitting diodes;where:M1 is a metal atom;carbene is a carbene ligand;L is a monoanionic or dianionic ligand;K is an uncharged monodentate or bidentate ligand selected from the group consisting of phosphines; CO; pyridines; nitriles and conjugated dienes which form a π complex with M1;n is the number of carbene ligands and is at least 1;m is the number of ligands L, where m can be 0 or ≧1;o is the number of ligands K, where o can be 0 or ≧1;where the sum n+m+o is dependent on the oxidation state and coordination number of the metal atom and on the denticity of the ligands carbene, L and K and also on the charge on the ligands carbene and L, with the proviso that n is at least 1, and alsoan OLED comprising these transition metal complexes, a light-emitting layer comprising these transition metal complexes, OLEDs comprising this light-emitting layer, devices comprising an OLED according to the present invention, and specific transition metal complexes comprising at least two carbene ligands.

主权项

1. An organic light-emitting diode comprising at least one uncharged transition metal complex of the formula (I) comprising at least one carbene ligand wherein the symbols have the following meanings: M1 is Ir in any oxidation state possible for the respective metal atom; carbene is a carbene ligand which may be uncharged or monoanionic and monodentate, bidentate or tridentate, with the carbene ligand also being able to be a biscarbene or triscarbene ligand; L is a monoanionic or dianionic ligand, which may be monodentate or bidentate; n is the number of carbene ligands, wherein n is at least 1 and when n>1 the carbene ligands in the complex of the formula I can be identical or different; m is the number of ligands L, wherein m can be 0 or ≧1 and when m>1 the ligands L can be identical or different; o is the number of ligands K, wherein o is 0; wherein the sum n+m+o is dependent on the oxidation state and coordination number of the metal atom and on the denticity of the ligands carbene, L and also on the charge on the ligands carbene and L, with the proviso that n is at least 1, wherein the carbene ligand or ligands has/have the formula II wherein the symbols have the following meanings: Do1 is S or 0; r is 0; p is 0; q is 0; Y1 and Y2 together form a bridge between the donor atom Do1 and the nitrogen atom N which has two atoms of which one is a carbon atom, and the other is a carbon or nitrogen atom; R1 and R2 together form a bridge having a total of from three to five atoms of which one or two atoms may be heteroatoms and the remaining atoms are carbon atoms, so that the group forms a five- to seven-membered, ring which may contain, in addition to the existing double bond, one further double bond or in the case of a six- or seven-membered ring two further double bonds and may be substituted by alkyl or aryl groups and may contain at least one heteroatom.