Table 1.

Reaction of substituted anilines with nitrosobenzene. Reagents and conditions: appropriate aniline (1.0 eq.), nitrosobenzene (1.0 eq.), AcOH (0.5 M), ambient temperature, 24 h.

Entry	R	Calculated Eoxa	σp+	Azobenzene % Yieldb	Azoxybenzene % Yieldb
1	p-NMe2	0.18	−1.70	34	45
2	p-NH2	0.38	−1.30	28	43
3	o-NH2	0.73	N/A	8	91
4	p-OMe	0.77	−0.78	≥95	5
5	2,6-dimethoxy	0.77	N/A	46	35
6	p-NHCO2tBu	0.80	N/A	87	6
7	p-OH	0.83	−0.92	34	69
8	o-OMe	0.93	N/A	82	13
9	p-Me	0.97	−0.31	95	≤5
10	o-NHCO2tBu	1.04	N/A	85	12
11	o-Et	1.08	N/A	77	20
12	p-I	1.16	0.14	≥95	≤5
13	H	1.20	0.00	≥95	≤5
14	o-Br	1.46	N/A	49	8
15	p-CO2Me	1.49	0.49	82	6
16	2,6-difluoro	1.55	N/A	12	≤5
17	p-CN	1.63	0.66	64	7
18	p-CF3	1.67	0.61	≥95	≤5
19	o-NO2	1.88	N/A	≤5	≤5
20	p-NO2	1.90	0.79	19	≤5

^aVolts vs. SHE.

^bYield determined by ¹H NMR using dibromomethane as an internal standard.

N/A = not available.