Study On The Interaction Of Cucurbiturils With1,8-naphthalimide Derivatives And Transmetil

In recent decades, supramolecular chemistry has become a hot field of chemical research. The cucurbit[n]uril family (CB[n] n=5-8,10) of macrocyclic host molecules have received considerable attention. CB[n] has a good application prospect in molecaular recognition, molecular catalysis, biological chemistry, pharmaceutical chemistry and so on.In this report, four kinds of1,8-naphthalimide derivatives were synthesized.We mainly study on the interaction between1,8-naphthalimide derivatives and cucurbit[n]uril(CB[n] n=7,8) by1H NMR, ESI-MS, UV-vis spectra and Fluorescence spectra. The results show that1,8-naphthalimide derivatives can enter into the cavity to form a host-guest complex with CB[n](n=7,8).As metal ions play an important role in environmental and biological processes, so the detection of metal ions is recently of signifcant importance. Nowadays, Fluorescence probe is one of the main methods for the detection of metal ions. In this paper, a new1,8-naphthalimide derivative L was designed and synthesized as fluorescent chemosensor, which exhibited high sensitivity, selectivity and real-time monitoring with fast response time. The fluorescent chemosensor L can selectively detect Cu2+and Co2+, Ni2+ions in aqueous solusion. In addition of Cu2+, Co2+and Ni to the water solution of L, the fluorescence of L is quenched. In the presence of the CB[6], the fluorescence intensity restored for Co2+and Ni2+. Whereas, the addition of CB[6] to the solution of L-Cu2+cann’t restore the fluorescence intensity. Therefore, L could be used as a fluorescent sensor of Cu2+.This paper investigated the interaction of Transmetil (SMT) and Cucurbit[n]uril(CB[n], n=7,8) by using1H NMR, COSY, HSQC and UV-Vis spectroscopy. The results show that the Transmetil was trapped into the cavity of CB[n](n=7,8) to form a1:1host-guest complex in which the binding position of CB[n](n=7,8) was different due to the size of their cavity. The banding modes of CB[8] with isomerous SMT are also different. The binding constants of SMT with CB[7] and CB[8] were measured by UV-Vis spectroscopy and found to be 2314L/mol,8000L/mol, indicating that CB[7] and CB[8] could be used as possible slow-released agents.