Aromatic compounds for organic electroluminescent devices

A compound including at least one structure of the formula (Ia) and/or (Ib):

• where the symbols and indices used are as follows:
• Z1, Z2 is the same or different at each instance and is N, P, B, Al, P(═O), P(═S), or Ga;
• Y1, Y2, Y3 is the same or different at each instance and is a bond, N(Ar), N(R), P(Ar), P(R), P(═O)Ar, P(═O)R, P(═S)Ar, P(═S)R, B(Ar), B(R), Al(Ar), Al(R), Ga(Ar), Ga(R), C═O, C(R)2, Si(R)2, C═NR, C═NAr, C═C(R)2, O, S, Se, S═O, or SO2;
• p2, p3 are the same or different and are 0 or 1;
• X is N, CR, or C if a Y1, Y2 or Y3 group binds thereto, with the proviso that not more than two of the X groups in one cycle are N;
• R is the same or different at each instance and is H, D, OH, F, Cl, Br, I, CN, NO2, N(Ar)2, N(R1)2, C(═O)N(Ar)2, C(═O)N(R1)2, C(Ar)3, C(R1)3, Si(Ar)3, Si(R1)3, B(Ar)2, B(R1)2, C(═O)Ar, C(═O)R1, P(═O)(Ar)2, P(═O)(R1)2, P(Ar)2, P(R1)2, S(═O)Ar, S(═O)R1, S(═O)2Ar, S(═O)2R1, OSO2Ar, OSO2R1, a straight-chain alkyl, alkoxy or thioalkoxy group having 1 to 40 carbon atoms or an alkenyl or alkynyl group having 2 to 40 carbon atoms or a branched or cyclic alkyl, alkoxy or thioalkoxy group having 3 to 20 carbon atoms, where the alkyl, alkoxy, thioalkoxy, alkenyl or alkynyl group may in each case be substituted by one or more R1 radicals, where one or more non-adjacent CH2 groups may be replaced by R1C═CR1, C≡C, Si(R1)2, C═O, C═S, C═Se, C═NR1, —C(═O)O—, —C(═O)NR1—, NR1, P(═O)(R1), —O—, —S—, SO or SO2, or an aromatic or heteroaromatic ring system which has 5 to 60 aromatic ring atoms and may be substituted in each case by one or more R1 radicals, or an aryloxy or heteroaryloxy group which has 5 to 60 aromatic ring atoms and may be substituted by one or more R1 radicals;
• at the same time, two R radicals may also together form a ring system;
• Ar is the same or different at each instance and is an aromatic or heteroaromatic ring system which has 5 to 60 aromatic ring atoms and may be substituted by one or more R1 radicals;
• at the same time, it is possible for two Ar radicals bonded to the same carbon atom, silicon atom, nitrogen atom, phosphorus atom or boron atom also to be joined together via a bridge by a single bond or a bridge selected from B(R1), C(R1)2, Si(R1)2, C═O, C═NR1, C═C(R1)2, O, S, S═O, SO2, N(R1), P(R1) and P(═O)R1;
• R1 is the same or different at each instance and is H, D, F, Cl, Br, I, CN, NO2, N(Ar′)2, N(R2)2, C(═O)Ar′, C(═O)R2, P(═O)(Ar′)2, P(Ar′)2, B(Ar′)2, B(R2)2, C(Ar′)3, C(R2)3, Si(Ar′)3, Si(R2)3, a straight-chain alkyl, alkoxy or thioalkoxy group having 1 to 40 carbon atoms or a branched or cyclic alkyl, alkoxy or thioalkoxy group having 3 to 40 carbon atoms or an alkenyl group having 2 to 40 carbon atoms, each of which may be substituted by one or more R2 radicals, where one or more non-adjacent CH2 groups may be replaced by —R2C═CR2—, —C≡C—, Si(R2)2, C═O, C═S, C═Se, C═NR2, —C(═O)O—, —C(═O)NR2—, NR2, P(═O)(R2), —O—, —S—, SO or SO2 and where one or more hydrogen atoms may be replaced by D, F, Cl, Br, I, CN or NO2, or an aromatic or heteroaromatic ring system which has 5 to 60 aromatic ring atoms, each of which may be substituted by one or more R2 radicals, or an aryloxy or heteroaryloxy group which has 5 to 60 aromatic ring atoms and may be substituted by one or more R2 radicals, or an aralkyl or heteroaralkyl group which has 5 to 60 aromatic ring atoms and may be substituted by one or more R2 radicals, or a combination of these systems;
• at the same time, two or more, preferably adjacent R1 radicals together may form a ring system;
• at the same time, one or more R1 radicals may form a ring system with a further part of the compound;
• Ar′ is the same or different at each instance and is an aromatic or heteroaromatic ring system which has 5 to 30 aromatic ring atoms and may be substituted by one or more R2 radicals;
• at the same time, it is possible for two Ar′ radicals bonded to the same carbon atom, silicon atom, nitrogen atom, phosphorus atom or boron atom also to be joined together via a bridge by a single bond or a bridge selected from B(R2), C(R2)2, Si(R2)2, C═O, C═NR2, C═C(R2)2, O, S, S═O, SO2, N(R2), P(R2) and P(═O)R2;
• R2 is the same or different at each instance and is selected from the group consisting of H, D, F, CN, an aliphatic hydrocarbyl radical having 1 to 20 carbon atoms or an aromatic or heteroaromatic ring system which has 5 to 30 aromatic ring atoms and in which one or more hydrogen atoms may be replaced by D, F, Cl, Br, I or CN and which may be substituted by one or more alkyl groups each having 1 to 4 carbon atoms;
• or two or more substituents R2 together may form a ring system;
• and
• wherein at least two R radicals form a fused ring together with the further groups to which the two R radicals bind, where the two R radicals form at least one structure of the formulae (RA-1) to (RA-12);
• where R1 has the definition set out above, the dotted bonds represent the sites of attachment to the atoms of the groups to which the two R radicals bind, and the further symbols have the following definition,
• Y4 is the same or different at each instance and is C(R1)2, (R1)2C—C(R1)2, (R1)C═C(R1), NR1, NAr, O or S;
• Ra is the same or different at each instance and is F, a straight-chain alkyl, alkoxy or thioalkoxy group having 1 to 40 carbon atoms or an alkenyl or alkynyl group having 2 to 40 carbon atoms or a branched or cyclic alkyl, alkoxy or thioalkoxy group having 3 to 20 carbon atoms, where the alkyl, alkoxy, thioalkoxy, alkenyl or alkynyl group may be substituted in each case by one or more R2 radicals, where one or more non-adjacent CH2 groups may be replaced by R2C═CR2, C≡C, Si(R2)2, C═O, C═S, C═Se, C═NR2, —O(═O)O—, —C(═O)NR2—, NR2, P(═O)(R1), —O—, —S—, SO or SO2, or an aromatic or heteroaromatic ring system which has 5 to 60 aromatic ring atoms and may be substituted in each case by one or more R2 radicals, or an aryloxy or heteroaryloxy group which has 5 to 60 aromatic ring atoms and may be substituted by one or more R2 radicals;
• or two Ra radicals together may form a ring system;
• s is 0, 1, 2, 3, 4, 5 or 6;
• t is 0, 1, 2, 3, 4, 5, 6, 7 or 8;
• v is 0, 1, 2, 3, 4, 5, 6, 7, 8 or 9.