The catalytic reactions of M(TPP)Cl (M = Fe (0, Mn (Z)), Fe(TMP)Cl (31, and Fe(TDCPP)Cl( 4) (H,TPP = 5,10,15,20tetraphenylporphyrin;
H ,TMP = 5,10,15,20-tetramesitylporphyrin; H,TDCPP = 5,10,15,20-tetrakis(2,6-dichlorophenyl)porphyrin) with 2,4-diaminotoluene (5) and p-phenylenediarnine (6) were carried out using t-BuOOH (3 M isooctane solution) as oxidant. With the former substrate, the nitro derivatives 2-amino-4-nitrotoluene @a) and 2,4-dinitrotoluene (5b) (total yield of 5a + 5b ranges between 27-55%) were obtained with low yields and their amounts depend on the catalyst used. An other oxidation product of 5 was 3-amino-4(tert-butyldioxy)-4-methyl-2,5-cyclohexadien-l-imine hydrochloride (5~) (20%). In the oxidation reaction of 6, 4-nitroaniline (6a) (11%) was obtained only with catalyst 1, being an unidentified black solid (6b) the major oxidation product. 6b was always the main product with all the studied catalysts (l-31, while the yields and nature of the recovered azobenzenes depend on the metalloporphyrin used: the highest yield of 4,4'-dinitroazobenzene (6c) (37%) was obtained with 3 in the presence of acetic acid, 4,4'-diaminoazobenzene (6d) (19%) was obtained with 4, and 4-amino,4'-nitroazobenzene (6e) (17%) with 3. The catalytic reactions of Mo(OXO,),(H,OXHMPA) (7) (HMPA = hexamethylphosphotriamide), with 5, 6, and 4-aminodiphenylamine (81, in the presence of H,O, (35% w/w water solution) as oxidant, were studied. The corresponding mononitro derivatives, 5a, 6a, and 4-nitrodiphenylamine (8a) were obtained with fair selectivity (35, 70, and 60%, respectively).