pseudorotaxane. Integration of pertinent signals allowed the associationconstants of pseudorotaxanes to be determined readily. Among the [22-30]crown ethers, the highest value of the associationconstant was that for the [24]crown ether/dibenzylammonium ion system; the [25-30]crown ether/ammonium ion systems exhibited moderate values of their associationconstants [K exp = 35-114 M -1 when using (ArCH 2 ) 2 NH