Encapsulation of 2,2′-(decane-1,10-diyl)-diisoquinoline into cucurbit[6]uril and α,α′,δ,δ′-tetramethyl-cucurbit[6]uril: formation of pseudorotaxanes and polypseudorotaxanes†

Abstract

Host–guest complexation of cucurbit[6]uril and α,α′,δ,δ′-tetramethyl-cucurbit[6]uril with 2,2′-(decane-1,10-diyl)-diisoquinolinium has been investigated by 1H NMR, UV and fluorescence spectroscopy in aqueous solution and by X-ray crystallography in solid state. Experimental data suggest that in the aqueous solution, both host molecules form [2]pseudorotaxanes with the host located over the decyl chain of the guest. In the solid state, neighbouring [2]pseudorotaxanes are linked by π⋯π and C–H⋯π interactions, eventually generating polypseudorotaxanes.