Probing Peripheral H-Bonding Functionalities in BN-Doped Polycyclic Aromatic Hydrocarbons

The replacement of carbon atoms at the zigzag periphery of a benzo[ fg ]tetracenyl derivative with an NBN atomic triad allows the formation of heteroatom-doped polycyclic aromatic hydrocarbon (PAH) isosteres, which expose BN mimics of the amidic N H functions. Their ability to form H-bonded complexes has never been touched so far. Herein, we report the first solution recognition studies of peripherally NBN-doped PAHs to form H-bonded DD·AA- and ADDA·DAAD-type complexes with suitable complementary H-bonding acceptor partners. The first determination of K a in solution showed that the 1:1 association strength is around 27 ± 1 M –1 for the DD·AA complexes in C 6 D 6, whereas it rises to 1820 ± 130 M –1 for the ADDA·DAAD array in CDCl 3 . Given the interest of BN-doped polyaromatic hydrocarbons in supramolecular and materials chemistry, it is expected that these findings will open new possibilities to design novel materials, where the H-bonding properties of peripheral N H hydrogens could serve as anchors to tailor the organizational properties of PAHs.