NOVELTY - 2,4-Diphenyl-quinoline iridium complex is new.    USE - As organic electroluminescent compound useful in organic electroluminescent device e.g. organic solar cell (claimed).    ADVANTAGE - The organic electroluminescent compound (I) (red phosphorescent compound) exhibits high luminous efficiency and improved lifetime. The compound has excellent properties as compared to those of conventional red phosphorescent materials. The compound is applicable to organic light emitting device (OLED) panels of medium to large size. The organic electroluminescent compound has excellent electroluminescent properties and thermal stability than conventional phosphorescent materials, provides higher quantum efficiency and lower operation voltage as compared to conventional materials. Thus, if an organic electroluminescent compound is applied to an OLED panel, further enhanced results are anticipated in development of OLED's having medium to large size. If the compound is applied to an organic solar cell as a material of high efficiency, more excellent properties are anticipated as compared to conventional materials. The dopant provides improvement in device life as well as luminous efficiency. The compound allows reduction of time for mass production of OLEDs, which give great benefit on its commercialization.    DETAILED DESCRIPTION - 2,4-Diphenyl-quinoline iridium complex of formula (I) is new.    L1=organic ligand;    R1-R5=H, 1-20C alkyl, 1-20C alkoxy, 3-12C cycloalkyl, halogen, tri-1-20C alkylsilyl or tri-6-20C arylsilyl;    R6=H, 1-20C alkyl, halogen or 6-20C aryl;    R11-R14=H, 1-20C alkyl, halogen, cyano, tri-1-20C alkylsilyl, tri-6-20C arylsilyl, 1-20C alkoxy, 1-20C alkylcarbonyl, 6-20C arylcarbonyl, di-1-20C alkylamino, di-6-20C arylamino, phenyl, naphthyl, anthryl, fluorenyl, spirobifluorenyl or 1',3'-dihydrospiro(fluorene-9,2'-indene) (alkyl, phenyl, naphthyl, anthryl, and fluorenyl groups are optionally substituted by at least one T1);    T1=1-20C alkyl (optionally substituted by halogen), 1-20C alkoxy, halogen, tri(1-20C)alkylsilyl, tri (6-20C)arylsilyl, (1-20C)alkylcarbonyl, (6-20C)arylcarbonyl, di(1-20C)alkylamino, di(6-20C)arylamino or 6-20C aryl);and    n=1-3.    Each of R11-R14 is optionally linked to another adjacent group from R11-R14 via 3-12C alkylene or 3-12C alkenylene with or without a fused ring to form an alicyclic ring, or a monocyclic or polycyclic aromatic ring (all optionally substituted by at least one T1). Provided that R11-R14 cannot be hydrogen at the same time. INDEPENDENT CLAIMS are included for the following:    (1) an organic electroluminescent device comprising a first electrode; a second electrode; at least one organic layer interposed between the first electrode and the second electrode, where the organic layer comprises an electroluminescent region comprising at least one compound (I); and at least one host selected from 1,3,5-tricarbazolylbenzene, polyvinylcarbazole, m-biscarbazolylphenyl, 4,4',4''-tri(N-carbazolyl)triphenylamine, 1,3,5-tri(2-carbazolylphenyl)benzene, 1,3,5-tris(2-carbazolyl-5-methoxyphenyl)benzene, bis(4-carbazolylphenyl)silane, and compounds of formulae (VI)-(VIII), and L1aL2M(Q1)y.    R91-R94=H, or T2 (alkyl, alkenyl, alkynyl, cycloalkyl, heterocycloalkyl, (hetero)aryl, arylsilyl, alkylsilyl, alkylamino, and arylamino are optionally substituted with at least one T2);    T2=halogen, 1-60C alkyl, 6-60C aryl, 4-60C heteroaryl, 5- or 6-membered heterocycloalkyl containing at least one heteroatom selected from N, O and S, 3-60C cycloalkyl, tri(1-60C)alkylsilyl, di(1-60C)alkyl-(6-60C)arylsilyl, tri(6-60C)arylsilyl, adamantyl, (7-60C)bicycloalkyl, 2-60C alkenyl, 2-60C alkynyl, cyano, 1-60C alkylamino, 6-60C arylamino, 6-60C aryl-1-60C alkyl, 1-60C alkyloxy, 1-60C alkylthio, 6-60C aryloxy, 6-60C arylthio, 1-60C alkoxycarbonyl, 1-60C alkylcarbonyl, 6-60C arylcarbonyl, carboxyl, nitro or hydroxyl;    L1a and L2=group of formula (Ia) or (Ib);    M= bivalent or trivalent metal;    y=0 or 1;    Q1=6-60C aryloxy or tri(6-60C)arylsilyl (both optionally substituted by 1-60C alkyl or 6-60C aryl);    X=O, S or Se;    ring A=oxazole, thiazole, imidazole, oxadiazole, thiadiazole, benzoxazole, benzothiazole, benzimidazole, pyridine or quinoline;    ring B1=pyridine or quinoline (both optionally substituted by phenyl or naphthyl (optionally substituted with 1-60C alkyl) or 1-60C alkyl);and    R101-R104=H or T2 (alkyl, alkenyl, alkynyl, cycloalkyl, heterocycloalkyl, (hetero)aryl, arylsilyl, alkylsilyl, alkylamino, or arylamino of ring A and R101-R104 are optionally substituted with at least one T2).    Each of R91-R94, or each of R101-R104 is optionally linked to an adjacent substituent via 3-60C alkylene or 3-60C alkenylene with or without a fused ring to form an alicyclic ring, or a monocyclic or polycyclic aromatic ring (all optionally substituted with at least one T2).