. Author manuscript; available in PMC: 2016 Dec 2.

Published in final edited form as: J Am Chem Soc. 2015 Nov 19;137(47):14959–14967. doi: 10.1021/jacs.5b08767

Table 1.

Complete Association Constants and Binding Energy for Receptors 1a–g at 298 K

	Cl⁻ ^a		Br⁻ ^a		I⁻ ^b		NO₃⁻ ^a

host (R)	K_a (M⁻¹)	ΔG (kcal mol⁻¹)	K_a (M⁻¹)	ΔG (kcal mol⁻¹)	K_a (M⁻¹)	ΔG (kcal mol⁻¹)	K_a (M⁻¹)	ΔG (kcal mol⁻¹)
1a (H)	6750 ± 600^c	−5.22 ± 0.05	1630 ± 120^c	−4.38 ± 0.04	150 ± 10^c	−2.97 ± 0.03	3310 ± 170	−4.80 ± 0.03
1b (NO₂)	24600 ± 3500	−5.99 ± 0.09	5830 ± 510	−5.13 ± 0.05	580 ± 30	−3.76 ± 0.03	10600 ± 800	−5.49 ± 0.04
1c (Cl)	7900 ± 1300	−5.32 ± 0.09	2680 ± 230	−4.67 ± 0.05	290 ± 10	−3.36 ± 0.03	5520 ± 640	−5.10 ± 0.07
1d (F)	6760 ± 620	−5.22 ± 0.05	2340 ± 180	−4.59 ± 0.05	240 ± 10	−3.25 ± 0.03	4810 ± 320	−5.02 ± 0.04
1e (tBu)	4560 ± 720	−4.99 ± 0.09	1370 ± 100	−4.28 ± 0.03	150 ± 10	−2.98 ± 0.04	2700 ± 420	−4.68 ± 0.09
1f (OMe)	4730 ± 240	−5.01 ± 0.03	1000 ± 70	−4.09 ± 0.04	170 ± 10	−3.02 ± 0.03	3060 ± 360	−4.75 ± 0.07
1g (NMe₂)	2660 ± 320	−4.67 ± 0.07	800 ± 40	−3.96 ± 0.03	100 ± 10	−2.74 ± 0.07	1720 ± 160	−4.41 ± 0.05

Determined using UV–vis titrations in H₂O-saturated CHCl₃; error is the standard deviation (SD) of at least three titrations.

Determined using ¹H NMR titrations in H₂O-saturated CDCl₃; error is the SD of at least two titrations. The minimum error is assumed to be 5% in cases where the SD is <5%.

Previously reported (ref 27).