Materials for electronic devices

A compound of the formula (I) or formula (II):

• where the symbols and indices occurring are defined as follows:
• Ar1, Ar2 and Ar3 are on each occurrence, identically or differently, an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which is optionally substituted by one or more radicals R1;
• Cz is on each occurrence, identically or differently, a group of the formula (A)
• in which the dashed lines represent possible bonding positions to Ar1 or X or to the central carbazole derivative;
• A is N or P;
• X is selected on each occurrence, identically or differently, and is —B(R1)—, —N(R1)—, —P(R1)—, —P(R1)3—, —P(═O)(R1)—, —C(R1)2—, —Si(R1)2—, C═O, C═NR1, C═C(R1)2, —O—, —S—, —Se—, —S(═O)— or —S(═O)2—;
• Y is on each occurrence, identically or differently, CRCz or N, or is C if a group X or Ar1 or Ar3 or Cz is bonded to this group;
• Z is on each occurrence, identically or differently, CRHetAr or N, where at least one Z per six-membered ring is equal to N;
• q is on each occurrence, identically or differently, 0 or 1, where, in the case where q=0, the two groups bonded to the group Ar1 or Ar3 in question are bonded directly to one another;
• s is on each occurrence, identically or differently, 0 or 1, with the proviso that at least one index s is equal to 1;
• x is on each occurrence, identically or differently, 0 or 1, where, in the case where x=0, the two groups bonded to the group X in question are bonded directly to one another;
• R1, RHetAr and RCz are on each occurrence, identically or differently, 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, a straight-chain alkyl, alkoxy or thioalkoxy group having 1 to 40 C atoms or a straight-chain alkenyl or alkynyl group having 2 to 40 C atoms or a branched or cyclic alkyl, alkoxy or thioalkoxy group having 3 to 40 C atoms, each of which is optionally substituted by one or more radicals R2, where one or more CH2 groups is optionally replaced by —R2C═CR2—, —Si(R2)2—, —Ge(R2)2—, —Sn(R2)2—, C═O, C═S, C═Se, C═NR2, —P(═O)(R2)—, —S(═O)—, —S(═O)2—, —N(R2)—, —O—, —S—, —C(═O)O— or —C(═O)NR2—, or an aromatic or heteroaromatic ring system having 5 to 60 aromatic ring atoms, which is optionally in each case be substituted by one or more radicals R2, or an aryloxy or heteroaryloxy group having 5 to 60 aromatic ring atoms, which is optionally substituted by one or more radicals R2, or an aralkyl or heteroaralkyl group having 5 to 60 aromatic ring atoms, which may in each case be substituted by one or more radicals R2;
• two or more substituents R1, RHetAr or RCz here is optionally linked to one another and may optionally form a mono- or polycyclic aliphatic, aromatic or heteroaromatic ring system;
• R2 is on each occurrence, identically or differently, H, D or an aliphatic, aromatic or heteroaromatic organic radical having 1 to 20 C atoms, in which, in addition, one or more H atoms is optionally replaced by D or F;
• two or more radicals R2 here is optionally linked to one another and may optionally form a mono- or polycyclic aliphatic, aromatic or heteroaromatic ring system.