IMPROVED METHOD OF PREPARING SULFONYL ISOCYANATES Russian patent published in 2001 - IPC

FIELD: chemical industry. SUBSTANCE: described is method of preparing sulfonyl isocyanates of formula: J-SO₂NCO wherein J is by reacting phosgene and sulfoneamide of formula: J-SO₂NH₂ which is introduced into reaction mixture containing inert solvent, catalyst and phosgene, and reaction is carried out in the presence of molar excessive amount of phosgene with respect to sulfoneamide. Method makes it possible to prepare isocyanates with yield of 93- 97% and to avoid carrying out by- reactions and forming impurities. EFFECT: improved preparation method. 4 cl, 7 ex, 1 tbl