Isocyanide dichloride

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An isocyanide dichloride. RNCCl2.svg
An isocyanide dichloride.

Isocyanide dichlorides are organic compounds containing the RN=CCl2 functional group. Classically they are obtained by chlorination of isocyanides. Phenylcarbylamine chloride is a well-characterized example.

Contents

Preparation and reactions

Chlorination of organic isothiocyanates is also well established: [1]

RN=C=S + 2 Cl2 → RN=CCl2 + SCl2

Alkylisocyanates are chlorinated by phosphorus pentachloride:

RN=C=O + PCl5 → RN=CCl2 + POCl3

Cyanogen chloride also chlorinates to give the isocyanide dichloride: [1]

ClCN + Cl2 → ClN=CCl2

Reactions

Isocyanide dichlorides participate in Friedel-Crafts-like reactions, leading, after hydrolysis, to benzamides:

RN=CCl2 + ArH → RN=C(Cl)Ar + HCl
RN=C(Cl)Ar + H2O → R(H)NC(O)Ar + HCl

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References

  1. 1 2 R. G. Guy (1977). "Syntheses and Preparative Applications of Thiocyanates". In Saul Patai (ed.). Cyanates and Their Thio Derivatives: Part 2, Volume 2. PATAI'S Chemistry of Functional Groups. p. 619-818. doi:10.1002/9780470771532.ch2.