Probing peripheral H-bonding functionalities in BN-doped polycyclic aromatic hydrocarbons

The replacement of carbon atoms at the zig-zag periphery of a benzo[fg]tetracenyl derivative with an NBN atomic triad allows the formation of heteroatom-doped PAHs isosteres, which expose BN mimics of the amidic NH 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 double H-bonded DD•AA and ADDA•DAAD-type complexes with suitable complementary H-bonding acceptor partners. The first determination of the Ka in solution showed that the 1:1 association strength is around 27 ± 1 M-1 for the DD•AA complexes in C6D6, whereas it rises to 1820 ± 130 M-1 for the ADDA•DAAD array in CDCl3. Given the interest of BN-doped polyaro-matic 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 NH hydrogens could serve as anchors to tailor the organiza-tional propert...