Organic luminescent materials containing cycloalkyl ancillary ligands

An electroluminescent device comprises an anode, a cathode, and an organic layer, disposed between the anode and the cathode, comprising a meal complex comprising a ligand La with formula 1:

• Wherein
• Ra1, Ra2, and Ra3 are each independently selected from the group consisting of hydrogen, deuterium, halogen, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 ring carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted arylalkyl group having 7 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a nitrile group, an isonitrile group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof;
• At least one of Ra1, Ra2, and Ra3 has a structure represented by formula 2:
• Wherein
• X1, X2, Y1, Y2 are each independently selected from the group consisting of CRR′, NR″, O, S, and combinations thereof;
• m, n, p, q are 1, 2, 3, or 4;
• When m, n, p, q are each independently selected from 2, 3 or 4, the corresponding plurality of X1 can be the same or different, the corresponding plurality of X2 can be the same or different, the corresponding plurality of Y1 can be the same or different, the corresponding plurality of Y2 can be the same or different;
• r is 0, 1, 2, or 3;
• R, R′, R″, R21 and R22 are each independently selected from the group consisting of hydrogen, deuterium, halogen, a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 20 ring carbon atoms, a substituted or unsubstituted heteroalkyl group having 1 to 20 carbon atoms, a substituted or unsubstituted arylalkyl group having 7 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms, a substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, a substituted or unsubstituted amino group having 0 to 20 carbon atoms, an acyl group, a carbonyl group, a carboxylic acid group, an ester group, a nitrile group, an isonitrile group, a sulfanyl group, a sulfinyl group, a sulfonyl group, a phosphino group, and combinations thereof;
• When r is 0, at least one of R21 and R22 is not hydrogen or deuterium.