p-Toluenesulfonyl Isocyanate

Introduction

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

References

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