Table 2.

FTIR measured equilibrium constants at 298 K for H-bonding of solvents with selected antioxidants (K_solv) and corresponding values calculated by Equation 1.

	Solvent	Ksolv/M−1		KSEa
5b	CH3CN	3.1 ± 0.2	0.49
	EtOAc	5.5 ± 0.3	0.55
	DMSO	116.1 ± 11.2	0.55
		averageb	0.55	12
6b	CH3CN	3.0 ± 0.3	0.49
	EtOAc	4.7 ± 0.5	0.53
	DMSO	95.0 ± 5.9	0.53
		averageb	0.53	7
7b	CH3CN	6.9 ± 1.8	0.60
	EtOAc	14.1 ± 0.9	0.68
	DMSO	285.0 ± 9.6	0.62
		average2	0.65	26

^aKSE = kinetic solvent effect, taken from data in Table 1. ^bAverage of the data in EtOAc and DMSO only, see text.