Benzo[3]urils and their Recognition to Metal Cations and Anions

Abstract A new macrocyclic compound, benzo[3]uril 1 , was synthesized in a facile manner, and displayed a unique fluorescence response upon recognition and binding of Cu 2+ , Fe 3+ , F − , and acetate. H NMR (Nuclear Magnetic Resonance) spectra confirmed that binding occurs through hydrogen bonds between hydroxyl groups on the benzo[3]uril 1 and F − or acetate anions. The successful synthesis of benzo[3]uril 2 demonstrates that modification of this macrocycle is relative easy, and the absence of an interaction with anions further supports the importance of hydrogen binding between benzo[3]uril 1 to F − and acetate. Infra‐red (IR) spectroscopy suggest the carboxyl groups of benzo[3]uril coordinate metal cations Cu 2+ and Fe 3+ .