Organic electroluminescent compound and organic electroluminescent device comprising the same

An organic electroluminescent compound represented by the following formula 2:

• M(L1)x(L2)y (2)
• in formula 2,
• M represents a metal having an atomic number greater than 40;
• x represents 1 or 2;
• y represents 1 or 2;
• the sum of x and y is the oxidation number of M;
• L1 represents the ligand represented by formula 1;
• in formula 1,
• ring A represents a substituted or unsubstituted benzene ring, or a substituted or unsubstituted pyridine ring;
• R, each independently, represents a substituted or unsubstituted (C1-C30)alkyl, a substituted or unsubstituted (C3-C30)cycloalkyl, a substituted or unsubstituted (C6-C30)aryl, or a substituted or unsubstituted (3- to 30-membered)heteroaryl;
• R1, each independently, represents hydrogen, deuterium, a substituted or unsubstituted (C1-C30)alkyl, a substituted or unsubstituted (C3-C30)cycloalkyl, a substituted or unsubstituted (C6-C30)aryl, or a substituted or unsubstituted (3- to 30-membered)heteroaryl;
• n represents an integer of 1 to 4, in which, if n is an integer of 2 or more, each of R1 may be the same or different;
• and wherein
• one or more hydrogen atoms in ring A, R, and R1 may be replaced with one or more deuterium atoms;
• and
• L2 represents the ligand represented by the following formula 3 or 4:
• in formulas 3 and 4,
• R4 to R8, each independently, represent hydrogen, deuterium, a substituted or unsubstituted (C1-C30)alkyl, a substituted or unsubstituted (C3-C30)cycloalkyl, a substituted or unsubstituted (C6-C30)aryl, or a substituted or unsubstituted (3- to 30-membered)heteroaryl;
• or R4 and R5, R5 and R6, adjacent R7's, and adjacent R8's, each independently, may be linked to each other to form a ring(s);
• and
• d and e, each independently, represent an integer of 1 to 4, in which, if d and e, each independently, are an integer of 2 or more, each of R7 and each of R8 may be the same or different.