Patent ID: 7154114

Claim:
A light emitting device, comprising: (a) an anode; (b) a cathode; (c) an organic layer disposed between the anode and the cathode, wherein the organic layer comprises a host and a dopant, and the host comprises a compound having at least one carbene atom coordinated to iridium, and the compound has the structure: wherein the dotted lines represent optional double bonds; ring A is independently an aromatic cyclic, heterocyclic, fused cyclic, or fused heterocyclic ring with at least one carbon atom coordinated to Ir, wherein ring A can be optionally substituted with one or more substituents Ra; R 1 is independently selected from hydrogen, alkyl, alkenyl, alkynyl, aralkyl, aryl, heteroaryl, substituted aryl, substituted heteroaryl, or a heterocyclic group; R 2 –R 5 , and Ra are independently selected from hydrogen, alkyl, alkenyl, alkynyl, aralkyl, CN, CF 3 , CO 2 R′, C(O)R′, C(O)NR′2, NR′2, NO 2 , OR′, SR′, SO 2 , SOR′, SO 3 R′, halo, aryl, heteroaryl, substituted aryl, substituted heteroaryl, or a heterocyclic group; and additionally or alternatively, two R or Ra groups on the same or adjacent ring, together form independently a 5 or 6-member cyclic group, wherein said cyclic group is cycloalkyl, cycloheteroalkyl, aryl, or heteroaryl; and wherein said cyclic group is optionally substituted by one or more substituents J; each substituent J is independently selected from the group consisting of R′, CN, CF 3 , C(O)OR′, C(O)R′, C(O)NR′ 2 , NR′ 2 , NO 2 , OR′, SR′, SO 2 , SOR′, or SO 3 R′, and additionally, or alternatively, two J groups on adjacent ring atoms form a fused 5- or 6-membered aromatic group; each R′ is independently selected from halo, H, alkyl, alkenyl, alkynyl, heteroalkyl, aralkyl, aryl, and heteroaryl; b is 0, 1, 2, or 3.