NOVELTY - Substituted heterocyclic compounds (I) or (II) are new.    USE - (I) or (II) or the oligomer, polymer or the dendrimer is useful as a matrix material in an emitting layer, as an electron transport material in an electron transport- or electron injection layer and as a hole blocking material in a hole blocking layer of electronic devices comprising organic electroluminescent devices (preferred), organic integrated circuits, organic field-effect transistors, organic thin film transistors, organic light-emitting transistors, organic solar cells, organic optical detectors, organic photoreceptors, organic field-quench devices, light-emitting electrochemical cells and organic laser diodes (all claimed).    ADVANTAGE - (I) exhibit high temperature and oxidation stability, and good processability. The device comprising (I) or (II) exhibits high efficiency and long service life, and operates at low operating voltage.    DETAILED DESCRIPTION - Substituted heterocyclic compounds of formula (I) or (II) are new.    R11 = heteroaryl with 5-14 aromatic ring atoms, keto, phosphorus oxide or sulfur oxide (all bonded to (I) directly or through L, and all optionally substituted by at least one group R2) or -CN;    L = -(Ar1)k-;    Ar1 = (hetero)arylene with 5-10 aromatic ring atoms (optionally substituted by at least one group R2);    k = 1-5;    X, Y1 = single bond, C(R1)2, NR1, PR1, P(O)R1, O, S, SO or SO2;    V1 = single bond, CO, CS, P(O)R1, SO or SO2;    T = single bond, C(R1)2, CO, CS, Si(R1)2, NR1, PR1, P(O)R1, O, S, SO or SO2;    Z = CR1 or N (when Z is not bonded to any group) or C (when Z is bonded to a group); either    R1 = 1-20C alkoxy or 1-20C (thio)alkyl (all linear) or 3-20C alkoxy or 3-20C (thio)alkyl (all branched or cyclic), 2-20C alkenyl, 2-20C alkynyl (where in all groups at least one CH2 group is optionally replaced by -R2C=CR2-, -CC-, Si(R2)2, C=O, C=S, C=NR2, -C(=O)O-, -C(=O)NR2-, NR2, P(=O)(R2), -O-, -S-, SO or SO2, and at least one H is optionally replaced by D, F, Cl, Br, I, CN or NO2), (hetero)aromatic ring with 5-30 aromatic ring atoms or (hetero)aryloxy with 5-30 aromatic ring atoms (all optionally substituted by at least one group R2), H, D, F, Cl, Br, I, B(OR2)2, CHO, C(=O)R2, CR2=C(R2)2, CN, C(=O)OR2, C(=O)N(R2)2, Si(R2)3, N(R2)2, NO2, P(=O)(R2)2, OSO2R2, OR2, S(=O)R2 or S(=O)2R2; or    at least 2 R1 = ring; either    R2 = 1-20C alkoxy or 1-20C (thio)alkyl (all linear) or 3-20C alkoxy or 3-20C (thio)alkyl (all branched or cyclic), 2-20C alkenyl, 2-20C alkynyl (where in all groups at least one CH2 group is optionally replaced by -R3C=CR3-, -CC-, Si(R3)2, C=O, C=S, C=NR3, -C(=O)O-, -C(=O)NR3-, NR3, P(=O)(R3), -O-, -S-, SO or SO2, and at least one H is optionally replaced by D, F, Cl, Br, I, CN or NO2), (hetero)aromatic ring with 5-30 aromatic ring atoms or (hetero)aryloxy with 5-30 aromatic ring atoms (all optionally substituted by at least one group R3), H, D, F, Cl, Br, I, B(OR3)2, CHO, C(=O)R3, CR3=C(R3)2, CN, C(=O)OR3, C(=O)N(R3)2, Si(R3)3, N(R3)2, NO2, P(=O)(R3)2, OSO2R3, OR3, S(=O)R3 or S(=O)2R3; or    at least 2 R2 = ring; either    R3 = aliphatic 1-20C organic group or (hetero)aromatic 1-20C organic group (in all groups at least one H is optionally replaced by D or F), H, D or F; or    at least 2 R3 = ring;    m = 0 or 1; and    n = 0 or 1.    Provided that: X and Y1 do not represent NR1, PR1, P(O)R1, O, S, SO or SO2; the group V1 is single bond, when at least one of the groups Z in the ring, which is bonded to V1, is nitrogen; both the indices m in (I) do not simultaneously represent 0; and both the indices n in (I) do not simultaneously represent 0. INDEPENDENT CLAIMS are also included for:    (1) oligomers, polymers or dendrimers comprising (I) or (II), where the bonds to the polymers, oligomers or dendrimers are localized at any position in (I) substituted with R1 or R2;    (2) a formulation comprising (I) or (II) or at least one above polymer, oligomer or dendrimer, and at least one solvent; and preparing (I).