ABSTRACT
Cucurbit[6]uril (CB[6]) with a substituent attached solely to one methylene bridge was prepared for the first time. The monosubstituted CB[6] undergoes self-assembly to form a cyclic tetramer in the solid state. The affinity of the monosubstituted CB[6] to a series of alkylammonium salts was measured revealing a minor effect of the substituent on the binding properties of the macrocycle.
ABSTRACT
Cucurbit[6]uril (CB6) and bispyridinium ethylene form a stable inclusion complex. A rotaxane derived from this complex was prepared in which a CB6 wheel shuttles along an axle in an NMR time-resolved regime.
Subject(s)
Bridged-Ring Compounds/chemistry , Ethylenes/chemistry , Imidazoles/chemistry , Pyridinium Compounds/chemistry , Rotaxanes/chemical synthesis , Magnetic Resonance Spectroscopy , Molecular Structure , Rotaxanes/chemistry , TemperatureABSTRACT
The supramolecular complex formed by partial inclusion of methylviologen in MeCB6 was described both in solution and in the solid state. The association constant of the complex was determined using (1)H NMR and UV-vis spectrophotometric titration. An extraordinary 2000-fold drop in the association constant of the complex was observed when pure water was replaced by 50 mM NaCl solution.