Toward interlocked molecules beyond catenanes and rotaxanes

[GRAPHICS] A linear bis secondary dialkylammonium ion containing scaffold-based upon a n anthracenyl core-has been synthesized. It has been demonstrated that it i s possible to dock either one or two dibenzo[24]crown-8 (DB24C8) macrocycle s onto this scaffold to afford either a [2]- or [3]pseudorotaxane, respecti vely, In solution, the association constants for the formation of each of t hese species has been quantified by employing H-1 NMR spectroscopy, and bot h species survive in the "gas phase" as evidenced by FAB mass spectrometry. Additionally, the X ray crystal superstructure of the [3]pseudorotaxane ha s been determined.