Electrospray mass spectral studies of aromatic diazonium salts and diazotates

Electrospray (ES) mass spectra were observed for a series of aryldiazonium cations and the intact ions were observed. Collisionally activated decompositions lead to facile loss of nitrogen to form the corresponding aryl cations. Comparisons of the proportion of intact and fragment ions for each cation at a constant collisional energy lead to an order of relative stability for the diazonium cations which is similar to that determined in solution by chemical methods. Negative‐ion ES mass spectra were observed for the intact ions for the corresponding diazotates. Like the diazonium cations, they also readily lose nitrogen in collisionally activated decompositions to give the phenolate anions [OAr] − .