Synlett 2004(14): 2644-2645  
DOI: 10.1055/s-2004-834832
© Georg Thieme Verlag Stuttgart · New York

p-Toluenesulfonyl Isocyanate

Jean-Baptiste Malaubier*
Chemistry Department, National University of Ireland, Galway, Ireland
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Further Information

Publication History

Publication Date:
20 October 2004 (online)


p-Toluenesulfonyl isocyanate (tosyl isocyanate or ­TsNCO) is a colorless liquid that reacts violently with ­water and with basic and protic solvents. Reactions should be carried out with care and only in a fumehood, since TsNCO is corrosive and lachrymatory. It is easily soluble in inert media such as chlorinated, aromatic and ethereal solvents. It is now commercially widely available but can also be synthesised in about 93% yield as shown in Scheme 1. [1]

The reactivity of the isocyanate carbon is greatly improved by the sulfonyl group nearby. TsNCO is remarkably heat-stable and can be distilled in vacuo without decomposition.

Scheme 1 Synthesis of TsNCO


  • 1a Ulrich H, and Sayigh AAR. inventors; U. S. Patent  3371114.  1968
  • 1b For a review see: Ulrich H. Chem. Rev.  1965,  65:  369 
  • 2 Ohe K. Matsuda H. Morimoto T. Ogoshi S. Chatani N. Murai S. J. Am. Chem. Soc.  1994,  116:  4125 
  • 3a Willis RR. Calligaris M. Faleschini P. Gallucci JC. Wojcicki A. J. Organomet. Chem.  2000,  593-594:  465 
  • 3b Shuchart CE. Willis RR. Wojcicki A. J. Organomet. Chem.  1992,  424:  185 
  • 4a Mastrolorenzo A. Scozzafava A. Supuran CT. Eur. J. Pharm. Sci.  2000,  11:  325 
  • 4b Scozzafava A. Supuran CT. Bioorg. Med. Chem. Lett.  2002,  12:  2667 
  • 5 Nussbaumer P. Geyl D. Horvath A. Lehr P. Wolff B. Billich A. Bioorg. Med. Chem. Lett.  2003,  13:  3673 
  • 6 McFarland JW. Beaulieu JJ. Arrey LN. Frey LM. J. Heterocycl. Chem.  1988,  25:  1431 
  • 7 Hamley P. Holmes AB. Kee A. Ladduwahetty T. Smith DF. Synlett  1991,  29 
  • 8 Xu D. Sharpless KB. Tetrahedron Lett.  1993,  34:  951