Patent ID: 7985492

Claim:
An electroluminescent compound of formula: wherein L is a ligand selected from the group consisting of (i) and (ii) as follows: and wherein: M is ruthenium, rhodium, palladium, osmium, iridium or platinum; n is 1 or 2; the number of ligands (i) or (ii) in the electroluminescent compound is determined by the valence of the metal M and the quantity n so as to form an electrically neutral compound; R 1 to R 5 which may be the same or different are selected from substituted and unsubstituted hydrocarbyl groups; substituted and unsubstituted monocyclic and polycyclic heterocyclic groups; substituted and unsubstituted hydrocarbyloxy or carboxy groups; fluorocarbyl groups; halogen; nitrile; nitro; amino; alkylamino; dialkylamino; arylamino; diarylamino; N-alkylamido, N-arylamido, sulfonyl and thiophenyl; and R 2 and R 3 can additionally be alkylsilyl or arylsilyl; p, s and t independently are 0, 1, 2 or 3; q and r independently are 0, 1 or 2, subject to the provisos that: where p is 2, one of the R 1 groups is selected from saturated hydrocarbyl and halogen and the other is as defined above; where p is 3, two of the R 1 groups are selected from saturated hydrocarbyl and halogen and the other is as defined above; where q is 2, one of the R 2 groups is selected from saturated hydrocarbyl and halogen and the other is as defined above; where r is 2, one of the R 3 groups is selected from saturated hydrocarbyl and halogen and the other is as defined above; where s is 2, one of the R 4 groups is selected from saturated hydrocarbyl and halogen and the other is as defined above; where s is 3, two of the R 4 groups are selected from saturated hydrocarbyl and halogen and the other is as defined above; where t is 2, one of the R 5 groups is selected from saturated hydrocarbyl and halogen and the other is as defined above; and where t is 3, two of the R 5 groups are selected from saturated hydrocarbyl and halogen and the other is as defined above.