Non-Planar Perylene Bisimide Analogues with Inserted Carbonyl and Methylene Subunits

Angew Chem Int Ed Engl. 2021 Jul 12;60(29):15838-15843. doi: 10.1002/anie.202104882. Epub 2021 Jun 11.

Abstract

The synthesis and properties of dinaphthotropone bisimide (DNTrBI) and dinaphthocycloheptatriene bisimide (DNCHepBI) are described. Their molecular design is conceptually based on the insertion of a carbon atom into a perylene bisimide (PBI) core. These molecules adopt non-planar structures due to the presence of a seven-membered ring. The PBI derivative into which a carbonyl group was inserted (DNTrBI) immediately underwent nonradiative decay and/or intersystem crossing in its excited state. The PBI derivative into which a methylene group was inserted (DNCHepBI) was susceptible to deprotonation on account of the two electron-withdrawing naphthalene monoimide units. Subsequent aerobic oxidation resulted in the formation of a C-C bond at the central methylene unit, thus affording a σ-dimer. The formation of this C-C bond is dynamically redox-active, i.e., electron injection into the σ-dimer almost quantitatively regenerated the deprotonated DNCHepBI.

Keywords: C−C bond cleavage; carbon; dyrex; non-planar π-systems; perylene bisimide.