NOVELTY - Electroluminescent device, comprises heterocyclic bridged biphenyl compounds (I).    USE - (I) is useful for solar cells, especially dye lasers and electroluminescent devices (claimed). (I) is useful in organic light emitting diodes.    ADVANTAGE - (I) may function with phosphorescent materials to provide improved efficiency, stability, manufacturability or special characteristics of electroluminescent devices. (I) improves the film morphology, electrical properties, light emission efficiency and life time of devices. (I) has good hole transporating properties and good electron-transporting properties.    DETAILED DESCRIPTION - Electroluminescent device, comprises heterocyclic bridged biphenyl compounds of formula (I).    A = 5-7-membered heteroaromatic ring comprising heteroatom of N, O or S, especially one N-atom and further heteroatom of N, substituted N, O or S;    Z1 = CH3-CH=CH-Ar1, -NA1A1a, -P(=O)A4A4a or -SiA6A7A8;    Z2 = CH3-CH=CH-Ar2, -NA2A2a, -P(=O)A5A5a or -SiA6aA7aA8a;    Ar1, Ar2 = 6-14C aryl, phenyl or naphthyl (all optionally substituted by 1-25C alkyl and optionally interrupted by -O- or 1-25C alkoxy); either    R1-R6 = H, halo or organic substituent; or    R1R2, R4R6, R2R3, R5R3, R5R6 = (hetero)aromatic ring or ring system (optionally substituted); either    R7 = organic substituent; or    R7R7 = (hetero)aromatic ring or ring system;    x = 0-5;    A1, A2, A1aA2a = 6-24C aryl, 2-30C heteroaryl (both all optionally substituted), -BU-N(A3)-A3a, substituted benzene moiety of formula (b) or biphenyl moiety of formula (c);    BU = fluorene moiety of formula (d); either    A3, A3a = 6-24C aryl or 2-30C heteroaryl (all optionally substituted); or    NA1A1a, NA2A2a, NA3A3a = heteroaromatic ring, ring system or diphenyl-amine compound of formula (e);    n = 0-2;    A4-A8, A4a-A8a = 6-24C aryl or 2-30C heteroaryl (all optionally substituted); either    R41 = Cl, F, CN, NR45R45a, 1-25C alkyl, 4-18C cycloalkyl, 1-25C alkoxy (in which one or more C-atoms which are not in neighbourhood to each other could be replaced by -NR45-, -O-, -S-, -C(=O)-O- or -O-C(=O)-O- or one or more H-atoms can be replaced by F, 6-24C aryl or 6-24C aryloxy, where one or more C-atoms can be replaced by O, S, or N or substituted by non-aromatic groups R41); or    R41R41 = ring system;    R45, R45a = H, 1-25C alkyl, 4-18C cycloalkyl (in which one or more C-atoms which are not in neighbourhood to each other could be replaced by -NR45b-, -O-, -S-, -C(=O)-O- or -O-C(=O)-O- or one or more H-atoms can be replaced by F, 6-24C aryl or 6-24C aryloxy, where one or more carbon atoms can be replaced by O, S, or N or substituted by non-aromatic groups R41); and    m = 0-3, preferably 0 or 1.    An INDEPENDENT CLAIM is included for a preparation of (I) comprises reacting phenanthrene compounds of formula (XX) with a compound of formula (HNA1A1) or diphenyl-amine compound of formula (XX1) in the presence of a base and a catalyst in a solvent.    Z1, Z2 = NA1A1 or (XX1);    n = 0-2;    X10 = Halo e.g. iodo; either    R1-R4 = H, (substituted)alkyl, aralkyl, aryl or heterocyclic; or    NR1R2, NR3R4 = a 5-7 membered ring;    R5-R7 = H atom, (substituted)alkyl, alkoxy, halo or nitro group.    Provided that phenazine compounds of formula (a) are excluded.