Bowl-Shaped Bispyrrole-Fused Perylene-diimide and Its Anions.

Incorporating two pyrrole subunits at the bay positions of perylene-diimide has been a long-pursued goal since 2009, but it has not been achieved due to high strain. Herein, via one step Buchwald-Hartwig reaction, PDI-2N was successfully generated with a bowl depth of 1.52 Å. Though with electron-rich pyrrole embedding, PDI-2N's radical anion and dianion were facilely prepared and were investigated both experimentally and theoretically. Moreover, PDI-2N crystallized in different manners under distinct conditions, and it formed tubular crystals with infinite two-directional columnar stacking under DMF conditions. This finding develops a dream bowl-shaped PDI derivative that holds great promise in organoelectronics.

Dimerized Nitrogen-Annulated Perylene Synthesized from 1,6-Diazecine as Chiral Emitter.

In this work, nitrogen-annulated perylene (NP) was dimerized into one framework connected by two nitrogen atoms, generating the target molecule of DNP-DA. Owing to the substructure of 1,6-diazecine ten-membered ring, DNP-DA illustrates helical chirality with moderate dissymmetry factor, elevated molecular levels, expanded conjugation and supramolecular interactions with acceptors etc. Notably, DNP-DA represents a limited example of nitrogen-perylene based CPL emitter with glum around 6×10-3 . Intrigued by the facile fabrication via a simple amination-cross coupling sequence and other above advancing features, this work demonstrates the potential generality of utilizing 1,6-diazecine as a chiral unit to build CPL-active materials.

Synthesis and Properties of Aza-Ovalene with Six Zigzag Edges.

Ovalene's nitrogenated derivative with all zigzag edges and nitrogen atom doping at the periphery has been developed via one-step nitrogenation of formylbisanthene. Because of nitrogen incorporation, these molecules show greatly decreased highest occupied molecular orbital levels, enhanced intermolecular interactions, and a reversible acid response. Aza-ovalene also exhibits a diatropic ring current along the periphery. This work provides rare examples of all-zigzag-edged N-polycyclic aromatic hydrocarbons.

Stable monovalent aluminum(i) in a reduced phosphomolybdate cluster as an active acid catalyst.

Low-valent aluminum Al(i) chemistry has attracted extensive research interest due to its unique chemical and catalytic properties but is limited by its low stability. Herein, a hourglass phosphomolybdate cluster with a metal-center sandwiched by two benzene-like planar subunits and large steric-hindrance is used as a scaffold to stabilize low-valent Al(i) species. Two hybrid structures, (H3O)2(H2bpe)11[AlIII(H2O)2]3{[AlI(P4MoV 6O31H6)2]3·7H2O (abbr. Al6{P4Mo6}6) and (H3O)3(H2bpe)3[AlI(P4MoV 6O31H7)2]·3.5H2O (abbr. Al{P4Mo6}2) (bpe = trans-1,2-di-(4-pyridyl)-ethylene) were successfully synthesized with Al(i)-sandwiched polyoxoanionic clusters as the first inorganic-ferrocene analogues of a monovalent group 13 element with dual Lewis and Brønsted acid sites. As dual-acid catalysts, these hourglass structures efficiently catalyze a solvent-free four-component domino reaction to synthesize 1,5-benzodiazepines. This work provides a new strategy to stabilize low-valent Al(i) species using a polyoxometalate scaffold.