NOVELTY - Substituted heteroaryl compounds (I) which do not comprise additional fused (hetero)aromatic ring having greater than 10 ring atoms, are new.    USE - (I) or the oligomers, polymers or dendrimers, or the compositions are useful as hole transport materials in hole transport- or hole injection layers, as matrix materials in emitting layers, as electron blocking materials or exciton blocking materials of electronic devices, preferably 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, organic laser diodes and organic electroluminescent devices (preferred) (all claimed).    ADVANTAGE - (I) ensure good efficiency, long service life and low operating voltage of the electronic devices.    DETAILED DESCRIPTION - Substituted heteroaryl compounds of formula (I) which do not comprise additional fused (hetero)aromatic ring having greater than 10 ring atoms, are new.    L = single bond or divalent (hetero)aryl with 12-40 ring atoms (optionally substituted by at least one group R2);    Ar1, Ar2 = (hetero)aromatic ring with 5-40 aromatic ring atoms (optionally substituted by at least one group R4); either    R1 = 1-20C alkoxy or 1-20C (thio)alkyl (both linear) or 3-20C alkoxy or 3-20C (thio)alkyl (both branched or cyclic) or 2-20C alkenyl or 2-20C alkynyl (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-, 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) or aromatic ring with 6-30 aromatic ring atoms (all optionally substituted by at least one group R2), H, D, F, Cl, Br, I, C(=O)R2, CN, Si(R2)3, NO2, P(=O)(R2)2, S(=O)R2 or S(=O)2R2, where R1 does not comprise additional amine groups; or    at least 2 R1 = ring; either    R4 = 1-20C alkoxy or 1-20C (thio)alkyl (both linear) or 3-20C alkoxy or 3-20C (thio)alkyl (both branched or cyclic) or 2-20C alkenyl or 2-20C alkynyl (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-, 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) or aromatic ring with 6-30 aromatic ring atoms (all optionally substituted by at least one group R2), H, D, F, Cl, Br, I, C(=O)R2, CN, Si(R2)3, NR2, NO2, P(=O)(R2)2, S(=O)R2 or S(=O)2R2; or    at least 2 R4 = ring; either    R2 = 1-20C alkoxy or 1-20C (thio)alkyl (both linear) or 3-20C alkoxy or 3-20C (thio)alkyl (both branched or cyclic) or 2-20C alkenyl or 2-20C alkynyl (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-, 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 group with 5-30 aromatic ring atoms (all optionally substituted by at least one group R3), H, D, F, Cl, Br, I, C(=O)R3, CN, Si(R3)3, NO2, P(=O)(R3)2, S(=O)R3 or S(=O)2R3;    at least 2 R2 = ring; either    R3 = H, D, F or aliphatic or (hetero)aromatic 1-20C organic group (in which at least one H is optionally replaced by D or F); or    at least 2 R3 = ring; and    X = N or CR1, where not greater than 2 X is N.    Provided that when L is single bond, then nitrogen in (I) is directly bonded to third position of heteroaryl moiety of (I); and when both Ar1 and Ar2 are phenyl, then at least one R4 on the phenyl is not hydrogen, and the group R4 on the phenyl comprises at least one (hetero)aromatic ring.    INDEPENDENT CLAIMS are also included for:    (1) preparing (I);    (2) an oligomer, polymer or a dendrimer comprising (I), where bonds to the polymer, oligomer or the dendrimer may be localized at arbitrary positions in (I) which are substituted with R1, R4 or R2;    (3) a composition comprising (I) and at least one further organic functional material comprising fluorescent emitter, phosphorescent emitter, host material, matrix material, electron transport material, electron injection material, hole transport material, hole injection material, electron blocking material or hole blocking material; and    (4) a formulation comprising (I), or the polymer, oligomer or the dendrimer, or the above composition, and at least one solvent.