Table 1.

Reduction potentials E_red(X^+·/X) of N-phenylphenothiazines 1–11 (determined by cyclic voltammetry using ferrocene as standard).

compound	E1(X+·/X)a	E2(X+·/X)	E1(X+·/X*)	E00b
1	0.75 V	1.50 Vc	−2.5 V	3.2 eV
2	0.57 V	1.00 V	−2.5 V	3.1 eV
3	0.73 V	1.49 V	−2.5 V	3.2 eV
4	0.71 V	–	−3.0 V	3.7 eVd
5	0.67 V	1.59 V	−2.5 V	3.1 eV
6	0.89 V	1.55 V	−2.1 V	3.0 eV
7	0.75 V	1.50 Vc	−2.5 V	3.3 eV
8	0.77 V	1.05 Vc	−2.6 V	3.4 eV
9	0.80 V	–	−2.6 V	3.4 eV
10	0.53 V	0.98 V	−2.9 V	3.4 eV
11	0.49 V	0.96 V	−2.9 V	3.4 eV

^aConverted from the ferrocene scale to the scale vs SCE: +0.38 V [30]. ^bE₀₀ was estimated by using the method of determination of the intersection of the normalized absorption and fluorescence. ^cIrreversible. ^dFluorescence in the UV-A range, see Figure S27 (Supporting Information File 1).