The reaction of isocyanates and isocyanates with bisulphite salts

Abstract

Organic isocyanates and isothiocyanates readily add bisulphite to form N-substituted aminooxomethanesulphonic acid salts (2), and the thioxo analogues respectively. As aryl isocyanates react rapidly with water, it is convenient to use triethylammonium bisulphite in an aprotic solvent for the addition. Aqueous solutions of these salts (2) are generally stable to storage although the alkyl derivatives are rather more stable than the aryl derivatives.