Studies on some triazene-1-oxide chelates of trivalent cobalt

It is shown from infrared and proton magnetic resonance (p.m.r.) data that the product of the reaction of N-methyl or N-ethyl hydroxylamine with an aryldiazonium salt is correctly represented as 1-methyl(or ethyl)-3-aryl-triazene-1-oxide which exists predominantly in the internally hydrogen-bonded from. P.m.r. spectra show that the tris-chelates of CoIII exist exclusively in the trans form. The nonexistence of the cis isomer is attributed to steric factors. The chelates show electronic transitions at ∼19,000 cm−1 and 29,400 cm−1. Probable assignments are briefly discussed