TY - JOUR

T1 - Electronic Materials

T2 - An Antiaromatic Propeller Made from the Four‐Fold Fusion of Tetraoxa[8]circulene and Perylene Diimides

AU - Pedersen, Viktor B. R.

AU - Pedersen, Stephan K.

AU - Jin, Zexin

AU - Kofod, Nicolaj

AU - Laursen, Bo W.

AU - Baryshnikov, Glib V.

AU - Nuckolls, Colin

AU - Pittelkow, Michael

PY - 2022

Y1 - 2022

N2 - The synthesis of an antiaromatic tetraoxa[8]circulene annulated with four perylene diimides (PDI), giving a dynamic non-planar π-conjugated system, is described. The molecule contains 32 aromatic rings surrounding one formally antiaromatic planarized cyclooctatetraene (COT). The intense absorption (ϵ=3.35×105 M−1 cm−1 in CH2Cl2) and emission bands are assigned to internal charge-transfer transitions in the combined PDI-circulene π-system. The spectroscopic data is supported by density functional theory calculations, and nuclear independent chemical shift calculation indicate that the antiaromatic COT has increased aromaticity in the reduced state. Electrochemical studies show that the compound can reversibly reach the tetra- and octa-anionic states by reduction of the four PDI units, and the deca-anionic state by reduction of the central COT ring. The material functions effectively in bulk hetero junction solar cells as a non-fullerene acceptor, reaching a power conversion efficiency of 6.4 %.

AB - The synthesis of an antiaromatic tetraoxa[8]circulene annulated with four perylene diimides (PDI), giving a dynamic non-planar π-conjugated system, is described. The molecule contains 32 aromatic rings surrounding one formally antiaromatic planarized cyclooctatetraene (COT). The intense absorption (ϵ=3.35×105 M−1 cm−1 in CH2Cl2) and emission bands are assigned to internal charge-transfer transitions in the combined PDI-circulene π-system. The spectroscopic data is supported by density functional theory calculations, and nuclear independent chemical shift calculation indicate that the antiaromatic COT has increased aromaticity in the reduced state. Electrochemical studies show that the compound can reversibly reach the tetra- and octa-anionic states by reduction of the four PDI units, and the deca-anionic state by reduction of the central COT ring. The material functions effectively in bulk hetero junction solar cells as a non-fullerene acceptor, reaching a power conversion efficiency of 6.4 %.

U2 - 10.1002/anie.202212293

DO - 10.1002/anie.202212293

M3 - Journal article

C2 - 36173989

VL - 61

JO - Angewandte Chemie International Edition

JF - Angewandte Chemie International Edition

SN - 1433-7851

IS - 48

M1 - e202212293

ER -