Juntaro Nogami

The development of a new building block for creating solution‐processable amorphous n‐type semiconductors provides a platform of fundamental importance for advanced organic electronic materials. We have recently demonstrated that oxidative inner‑bond cleavage of readily available dibenzo[ g , p ]chrysene affords a chiral figure‑eight macrocycle that bears electron‑withdrawing carbonyl groups, namely cyclobisbiphenylenecarbonyl (CBBC). In this study, we report a highly electron‑accepting derivative of CBBC (CBBC‑TIC), in which the CBBC core is connected to four electron‑withdrawing dicyanomethylene‑3‑indanone (IC) units via thiophene spacers. The distinctive X‑shaped molecular structure of CBBC‑TIC enables the solution‐process fabrication of a homogeneous amorphous film with good electron conductivity. Perovskite solar cells that contain CBBC‑TIC as the electron‐transport layer achieved a power conversion efficiency of 20.6%, which is comparable to that obtained with the benchmark fullerene derivative [6,6]‐phenyl‐C ₆₁ ‐butyric acid methyl ester (PCBM). Furthermore, the enantiomers of CBBC‐TIC exhibited spin‐selective electron transport arising from the chirality‐induced spin‐selectivity (CISS) effect, with remarkably high enantiospecific magnetic conductance asymmetry values of up to 80% in amorphous films. These findings demonstrate that CBBC represents a versatile molecular component for the creation of advanced non‑fullerene n‐type semiconductors.

The development of a new building block for creating solution‐processable amorphous n‐type semiconductors provides a platform of fundamental importance for advanced organic electronic materials. We have recently demonstrated that oxidative inner‑bond cleavage of readily available dibenzo[ g , p ]chrysene affords a chiral figure‑eight macrocycle that bears electron‑withdrawing carbonyl groups, namely cyclobisbiphenylenecarbonyl (CBBC). In this study, we report a highly electron‑accepting derivative of CBBC (CBBC‑TIC), in which the CBBC core is connected to four electron‑withdrawing dicyanomethylene‑3‑indanone (IC) units via thiophene spacers. The distinctive X‑shaped molecular structure of CBBC‑TIC enables the solution‐process fabrication of a homogeneous amorphous film with good electron conductivity. Perovskite solar cells that contain CBBC‑TIC as the electron‐transport layer achieved a power conversion efficiency of 20.6%, which is comparable to that obtained with the benchmark fullerene derivative [6,6]‐phenyl‐C ₆₁ ‐butyric acid methyl ester (PCBM). Furthermore, the enantiomers of CBBC‐TIC exhibited spin‐selective electron transport arising from the chirality‐induced spin‐selectivity (CISS) effect, with remarkably high enantiospecific magnetic conductance asymmetry values of up to 80% in amorphous films. These findings demonstrate that CBBC represents a versatile molecular component for the creation of advanced non‑fullerene n‐type semiconductors.

Core annulation of naphthalene diimide (NDI) represents a powerful strategy to modulate its electronic structure and solid-state organization. Here, we report the first pyrrole-fused NDI (NDPI) framework and elucidate its structural and electronic characteristics. Single-crystal X-ray diffraction reveals a highly planar π-core with short π–π stacking distance (3.33 Å) and strong intermolecular N–H···O hydrogen bonding (2.07 Å), highlighting the unique supramolecular features introduced by pyrrole annulation. Building on this motif, a series of donor–acceptor polymers was synthesized and systematically evaluated in OFET devices. The polymers exhibit optical bandgaps of 1.32–1.39 eV. Device mobilities range from 0.10 to 0.59 cm2 V–1 s–1, with charge transport behavior tunable from balanced ambipolar to unipolar n-type depending on donor strength. Correlation of AFM and GIWAXS analyses suggests that charge mobility is governed not solely by crystallinity, but by the interplay between π–π stacking and domain connectivity. This work establishes NDPI as a versatile building block for high-performance organic semiconductors.

The lateral π‐extension of helicenes would yield interesting physical properties derived from the enhanced π‐stacking ability as well as intrinsic helical chirality. Here we report the regiodivergent synthesis of hexabenzocoronene (HBC)‐based [6]helicenes via cationic rhodium(I)/segphos complex‐mediated intramolecular [2+2+2] and [2+1+2+1] cycloadditions of triynes followed by Scholl reaction. The resulting HBC‐based [6]helicenes possess stable helical chirality but more planar structure than previously reported HBC‐based [7] and [9]helicenes. Therefore, these HBC‐based [6]helicenes exhibit π‐stacking‐induced chiral self‐recognition in solution, allowing the measurement of enantiomeric ratios by¹H NMR spectroscopy without any chiral additive.