Synthesis, Characterization, and Electrochemical Study of Tetradentate Ruthenium-Schiff Base Complexes: Dioxygen Activation with a Cytochrome P450 Model Using 1- or 2-Methylimidazole as Axial Bases

Table 4

Electrochemical characteristics of the Ru(III)-complexes 1, 2, and 3 in presence of 1- and 2-methylimidazole under N₂ then under O₂ atmosphere.

Complex	𝐸1/2 (mV)^a	Δ𝐸p (mV)	𝐼pc1 (μA)	𝐼pc2 (μA)	𝐼pa/𝐼pc	𝐼pc(O2)/𝐼pc(N2)^b
Electrochemical characteristics of the Ru(III)-complexes
With 1-methylimidazole
1	580 (622)	70 (70)	6.4 (10.0)	— (1.2)	0.75	1.75
2	520 (565)	75 (75)	5.6 (11.6)	— (2.0)	0.82	2.42
3	500 (507)	65 (65)	8.8 (14.8)	— (2.0)	0.86	1.90
With 2-methylimidazole
1	580 (622)	70 (70)	6.6 (16.6)	— (0.0)	0.80	2.51
2	520 (565)	70 (70)	6.4 (20.9)	— (0.0)	0.82	3.26
3	500 (507)	75 (75)	9.6 (32.5)	— (0.0)	0.88	2.45

^a𝐸_1/2; values obtained under nitrogen.
^b𝐼_pc=(𝐼_pc1+𝐼_pc2); values given between brackets are obtained under oxygen.