Record Rate Enhancements for Tetrathiafulvalene Guests in the Formation of Bipyridinium- and Diazapyrenium-Based [2]Pseudorotaxanes.

The catalytic effects of guests 5-7 on the cyclization of 1 and 3 have been measured at 62 °C in MeCN. A record rate acceleration of more than 2000 times has been observed in the cyclization of the tricationic host 3 featuring large diazapyrenium π-surfaces by tetrathiafulvalene guests 6 and 7. The results emphasize the role played by extended π-surfaces in the host and the goodness of a tetrathiafulvalene core in the guest, enhanced by polyethereal side arms.