NOVELTY - Electronic device comprises metal complexes having azaborole ligands (I), where (I) contains a partial structure (M(L)n).    USE - The metal complexes (I) are useful as emitting compounds, matrix materials, hole blocking material and/or electron transport material in a electronic devices, which are organic electroluminescent devices, organic field-effect transistors, organic thin film transistors, organic light-emitting transistors, organic integrated circuits, organic solar cells, organic field-quench devices, light-emitting electrochemical cells, organic photoreceptors and organic laser diodes (O-laser). The compounds (V), (VI) or (VII) are useful as ligands for the production of the compounds (I) (all claimed).    ADVANTAGE - The metal complexes (I): have a high thermal stability and high durability as emitting material; are accessible with blue phosphorescent devices, which shows good color coordinates and long life; used in organic electroluminescent devices lead to high efficiencies and steep current-voltage curves.    DETAILED DESCRIPTION - Electronic device comprises metal complexes having azaborole ligands of formula (M(L)n(L1)m(L2)o) (I), where (I) contains a partial structure (M(L)n) of formula (II), (III) and/or (IV).    M = metal;    Y1 = NR3, O or S;    X = CR1 or N;    R1 = H, D, F, Cl, Br, I, CHO, N(R2)2, N(Ar)2, C(=O)Ar, P(=O)(Ar)2, S(=O)Ar, S(=O)Ar, CR2=C(R2)2, CR2=CR2Ar, CN, NO2, Si(R2)3, B(OR2)2, B(R2)2, B(N(R2) 2)2, OSO2R2, straight chain alkyl-, alkoxy- or thioalkoxy with 1-40C or a straight chain alkenyl- or alkynyl with 2-40C or a crosslinked or cyclic alkyl-, alkenyl-, alkynyl-, alkoxy- or thioalkoxy with 3-40C, which can be respectively substituted with at least one R2, where at least one non adjacent CH2 groups can be replaced by R2C=CR2, CC, Si(R2)2, Ge(R2)2, Sn(R2)2, C=O, C=S, C=Se, C=NR2, P(=O)(R2), SO, SO2, NR2, O, S or CONR2 and where at least one H can be replaced by D, F, Cl, Sr, I, CN or NO2, or an aromatic or heteroaromatic ring system with 5-60 aromatic ring atoms, which can be respectively substituted by at least one R2, and/or aryloxy- or heteroaryloxy with 5-60 aromatic ring atoms, which can be substituted by at least one R2, where two or more adjacent substituents R1 also with one another form a mono or polycyclic, aliphatic or aromatic ring system;    R2 = H, D, F or aliphatic, aromatic and/or heteroaromatic hydrocarbon with 1-20C, in which also at least one H can be replaced by F, thus two or more substituents R2 also with one another form a mono- or polycyclic, aliphatic or aromatic ring system; either    R3 = H, D, aliphatic hydrocarbon with 1-20C or aromatic or heteroaromatic ring system with 5-30 aromatic ring atoms, which can be substituted by at least one R1; or    R3 = coordinating group, where R3 binds over a charged or uncharged exocyclic or endocyclic donor atom D to the metal M, thus more partial ligands L with one another and/or L with L1 and/or L2, optionally over a link via R3, together form a polydentate and/or polypodal ligands;    Ar = aromatic or heteroaromatic ring system with 5-30 aromatic ring atoms, which can be substituted with at least one non-aromatic R1;    L1, L2 = co-ligands; either    n = 1-6;    o = 0-5; and    m = 0-5, when M has coordination number 6; or    n = 1-5;    o = 0-4; and    m = 0-4, when M has coordination number 5; or    n = 1-4;    m = 0-3; and    o = 0-3, when M has coordination number 4.    INDEPENDENT CLAIMS are also included for:    (1) the metal complexes having azaborole ligands (I);    (2) a boron-nitrogen containing heterocyclic compounds of formulae (V), (VI) or (VII), with the exclusion of 2,2-dichloro-1,3-di(2,4-dimethyl-phenyl)-4,5-dimethyl-(1,3,2)diazaborole of formula (VIII) and 2-chloro-1,3-diphenyl-(1,3,2)diazaborolidine; and    (3) preparing the compounds (I), comprising reacting a ligand (L) and optionally further ligands L1 and L2 with a metal alcoholate of formula (M(OR2)r), with metal ketoketonates of formula (IX) or metal halide of formula (MHalr), where the metal ketoketonates or metal halide may also be charged and contain at least one counter ion; the metal alcoholate, metal ketoketonates and metal halide (preferred) are present as a hydrate.    Hal = F, Cl, Br or I;    Lig = neutral or monoanionic, monodentate or bidentate ligand;    q = 0-4, preferably 0-2; and    r = 1-5.