Table 1.

Binding constants (K, M⁻¹) and binding energies (E) for the anion complexes of 1 as determined from UV-Vis titrations in DMSO.

Anions	Ka/M−1	Eb, kcal/mol
F−	7500	61.8
Cl−	5640	37.0
Br−	3560	32.0
I−	3030	c
HSO4−	9840	35.9
H2PO4−	6580	43.3
NO3−	2500	37.3
ClO4−	1485	31.8

^aBinding constants determined by UV-Vis titrations in DMSO (error limit is less than 20%);

^bbinding energy obtained from DFT calculations;

^cthe 6-31+G(d,p) basis set is not available for iodide.