Reduction potentials in water at pH 7 (in mV, vs. NHE), k^ET/k^HAT ratio, and k^ET (in M⁻¹ s⁻¹) for phenols 1, 2, 3, and 5.

phenol	k ET/kHAT	k ET	E 0
1	1.5 × 106	8.8 × 103	970a
2	1.4 × 105	8.9 × 102b	1060a
3	5.4 × 104	3.1 × 106	617c
5	1.6 × 104	3.7 × 105	290d

^aFrom ref. 14 In the same work redox potentials (at pH > 12) for 1˙/1⁻ and 2˙/2⁻ are 790 mV, and 1000 mV, respectively.¹⁴

^bThis is the upper value, the lower k^ET can be 35 M⁻¹ s⁻¹, see explanation in the text.

^cMeasured in water with Britten–Robinson buffer vs. Hg|Hg₂SO₄|K₂SO₄ electrode and recalculated into NHE.¹⁷

^dFrom ref. 18. This value is very close to E⁰ for quercetin at pH 7.¹⁹