Maximizing Coordination Capsule-Guest Polar Interactions in Apolar Solvents Reveals Significant Binding.
Guest encapsulation underpins the functional properties of self-assembled capsules yet identifying systems capable of strongly binding small organic molecules in solution remains a challenge. Most coordination capsules rely on the hydrophobic effect to ensure effective solution-phase association. In contrast, we show that using non-interacting anions in apolar solvents can maximize favorable interactions between a cationic Pd2L4host and charge-neutral guests resulting in a dramatic increase in binding strength. With quinone-type guests, association constants in excess of 108m-1were observed, comparable to the highest previously recorded constant for a metallosupramolecular capsule. Modulation of optoelectronic properties of the guests was also observed, with encapsulation either changing or switching-on luminescence not present in the bulk phase.
EaStCHEM School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, UK.
David P
0000-0002-4049-0759
DP
August
EaStCHEM School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, UK.
Gary S
GS
Nichol
EaStCHEM School of Chemistry, Joseph Black Building, David Brewster Road, Edinburgh, EH9 3FJ, UK.
Paul J
0000-0001-8418-5687
PJ
Lusby
coordination capsules; host-guest systems; non-coordinating anions; quinones; self-assembly