I will have some samples of azobisisobutyronitrile and I want to perform Barton-McCombie reaction. The problem is that the reagent is quite old and I need to know whether it has not decomposed.
Do you know any kind of test that I could perform? I was thinking if benzophenone in THF would not become blue after addition of fresh AIBN which would indicate the presence of the radicals. But I am not sure if such a test would be a good idea.