NOVELTY - Substituted heterocyclic compounds (I) are new.    USE - (I) are useful in composition for an emission layer (preferred), electron transport layer and in a hole blocking layer of electronic device including organic electroluminescent device preferably organic light emitting diode, organic light-emitting electrochemical cell, organic integrated circuits, organic field effect transistors, organic thin film transistors, organic solar cells, organic optical detectors, organic photoreceptors, organic light-emitting transistors, organic field-quench devices and organic laser diodes in medicine for phototherapy, preferably for phototherapy of skin (all claimed).    ADVANTAGE - (I) have good solubility, low sublimation temperature, high temperature stability oxidation stability and glass transition temperature, sublimate without residue, and provide organic electronic device with low production cost, high efficiencies, low operating voltages and long lifetimes.    DETAILED DESCRIPTION - Substituted heterocyclic compounds of formula (I) are new.    ETG = organic electron-transporting group from group of electron-deficient heteroaromatic groups, preferably heteroaryl group having 5-60C aromatic ring atoms, where N represents preferred heteroatoms (optionally substituted by R1), preferably triazines, pyrimidines, pyrazines, pyridines (all preferred), quinazolines, benzimidazoles, quinolines, isoquinolines or naphthyridines;    W1 = an electron rich organic group that conducts holes, preferably arylamines, triarylamines, bridged amines including dihydroacridine, dihydrophenazines, phenoxazione and phenothiazines, carbazoles, bridged carbazoles, biscarbazole, benzocarbazole, indenocarbazole or indolocarbazoles (all optionally substituted by R1);    V1 = O or S, preferably O;    Y1 (divalent bridge) = aromatic or heteroaromatic ring system having 5-60 ring atoms, preferably 5-10 aromatic ring atoms, if the bridge has exactly 6 ring atoms, then bridge represents a phenylene;    n = 0 or 1, preferably 0, where n is equal to 0, then ETG and ring B1 are directly linked by a single bond;    r = 0-3, preferably 0;    s = 0-3, preferably 0;    R1 = straight-chain alkyl, alkoxy or thioalkoxy having 1-40C, straight chain alkenyl or alkynyl having 2-40C, branched or cyclic alkyl, alkenyl, alkynyl, alkoxy, alkylalkoxy or thioalkoxy having 3-40C (all optionally substituted by R2) (where at least one non-adjacent CH2 group is optionally replaced by R2C=CR2, C(C), 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 at least one H atom is optionally replaced by D, F, Cl, Br, I, CN or NO2), aryloxy, arylalkoxy or heteroaryloxy having 5-60 aromatic ring atoms and/or diarylamino, diheteroarylamino or arylheteroarylamino groups having 10-40 aromatic ring atoms (all optionally substituted by R2), where at least two adjacent R2 are fused together to form a mono- or polycyclic, aliphatic or aromatic ring system), cross-linkable group Q, H, D, F, Cl, Br, I, N(R2)2, CN, NO2, Si(R2)3, B(OR2)2, C(=O)R2, P(=O)(R2)2, S(=O)R2, S(=O)2R2 or OSO2R2;    R2 = straight-chain alkyl, alkoxy or thioalkoxy having 1-40C, straight chain alkenyl or alkynyl having 2-40C, branched or cyclic alkyl, alkenyl, alkynyl, alkoxy, alkylalkoxy or thioalkoxy having 3-40C (all optionally substituted by R3) (where at least one non-adjacent CH2 group is optionally replaced by R3C=CR3, C(C), Si(R3)2, Ge(R3)2, Sn(R3)2, C=O, C=S, C=Se, C=NR3, P(=O)(R3), SO, SO2, NR3, O, S or CONR3 and at least one H-atom is optionally replaced by D, F, Cl, Br, I, CN or NO2), aromatic or heteroaromatic ring system having 5-60 aromatic ring atoms, aryloxy, arylalkoxy or heteroaryloxy having 5-60 aromatic ring atoms and/or diarylamino, diheteroarylamino or arylheteroarylamino groups having 10-40 aromatic ring atoms (all optionally substituted by R3) (where at least two adjacent R2 are fused together to form mono- or polycyclic, aliphatic or aromatic ring system), H, D, F, Cl, Br, I, N(R3)2, CN, NO2, Si(R3)3, B(OR3)2, C(=O)R3, P(=O)(R3)2, S(=O)R3, S(=O)2R3 or OSO2R3;    R3 = 1-20C aliphatic, aromatic and/or heteroaromatic hydrocarbyl (where at least one H-atom is optionally replaced by F), H, D or F, where at least two R3 are fused together to form mono- or polycyclic, aliphatic or aromatic ring system;    R4, R5 = H, D, F, Cl, Br, I, N(R2)2, CN, NO2, Si(R2)3, B(OR2)2, C(=O)R2, P(=O)(R2)2, S(=O)R2, S(=O)2R2, OSO2R2, straight-chain alkyl, alkoxy or thioalkoxy having 1-40C, straight-chain alkenyl or alkynyl having 2-40C or branched or cyclic alkyl, alkenyl, alkynyl, alkoxy, alkylalkoxy or thioalkoxy having 3-40C; and    Q = not defined.    INDEPENDENT CLAIMS are also included for:    (1) composition comprising (I) and at least one further compound including fluorescent emitters, phosphorescent emitters, host materials, matrix materials, electron-transporting materials, electron injection materials, hole conductor materials hole injection materials, electron blocking materials and hole-blocking materials;    (2) formulation comprising (I) or the composition and at least one solvent; and    (3) manufacturing electronic device comprising applying at least one organic layer by vapor deposition or from solution.