Fluorescent organic light emitting elements having high efficiency

An organic light-emitting element, comprising a light-emitting layer comprising

• i) a compound of formula
• as guest and a host material;
• or
• ii) a compound of formula
• as host and a fluorescent guest material, wherein
• R1, R2, R3 and R4 are independently of each other H, D, F, Cl, a C1-C25alkyl group, a C1-C25alkoxy group, a C6-C10aryloxy group, or a donor group of formula
• R5, R6, R7, R8 and R9 are independently of each other H, D, F, Cl, a C1-C25alkyl group, a C1-C25alkoxy group, a C6-C10aryloxy group, a group of formula
• (Xa), (Xb), or (Xd);
• R1′, R2′, R3′ and R4′ are independently of each other H, D, F, Cl, a C1-C25alkyl group, a C1-C25alkoxy group, or a C6-C10aryloxy group;
• or
• R1 and R2 together form a group of formula
• R1′ and R2′ together form a group of formula
• R3 and R4 together form a group of formula
• R3′ and R4′ together form a group of formula
• R5 and R6 together form a group of formula
• and/or
• R8 and R9 together form a group of formula
• A1, A2, A3, A4, A5, A6, A7 and A8 are independently of each other H, D, F, Cl, a C1-C25alkyl group, or a donor group of formula (Xa), (Xb), or (Xd);
• A9, A10, A11, A12, A13, A14, A15 and A16 are independently of each other H, D, F, Cl, a C1-C25alkyl group, or a donor group of formula (Xa), (Xb), or (Xd);
• X1 and X2 are independently of each other a single bond, O, S, N(R15), C(═O), C(R16)(R17), B(R18), or Si(R19)(R20) and
• R10, R11, R12, R21 and R21′ are independently of each other H, D, F, Cl, or a C1-C25alkyl group;
• R15, R16, R17, R18, R19 and R20 are independently of each other H, D, a C1-C25alkyl group, or a C6-C14aryl group, which can optionally be substituted by one, or more groups selected from a C1-C25alkyl group, a C1-C25alkoxy group and a C6-C10aryloxy group;
• with the proviso that at least one donor group of formula (Xa), (Xb), or (Xd) is present in the compound of formula (I);
• characterized in that it emits delayed fluorescence.