[Humr]

Hello. I would like to ask, if somebody knows how to determine quality of Diphenylphosphoryl azide. I have old bottle of it and i would like to know if its bad or not. My first idea is LC/MS, but i am not sure if its stable enough. Second idea is some reaction which runs very well with it.

[rolnor]

Its normaly a stable reagent, I think NMR would be best, its not stable to protic conditions like MeOH, H2O etc. normaly used as mobile phase for LC-MS.