Diazald


Diazald is used as a relatively safe and easily handled precursor to diazomethane, which is toxic and unstable. Diazald has become the favored commercially available precursor for the synthesis of diazomethane, compared to reagents like N-methyl-N-nitrosourea and N-methyl-N'-nitro-N-nitrosoguanidine, which are less thermally stable and more toxic and mutagenic, respectively.
Upon the addition of a base such as sodium hydroxide or potassium hydroxide and mild heating in a mixture of water, diethyl ether, and a high boiling polar cosolvent, the N-nitrososulfonamide undergoes successive elimination reactions to produce diazomethane as well as a p-toluenesulfonate salt as a byproduct, according to the following mechanism:
Like other nitroso compounds, it is thermally sensitive, as a result of its weak N–NO bond whose bond dissociation energy was measured to be 33.4 kcal/mol.