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.
Preparation and reactions.
Chlorination of organic isothiocyanates is also well established: 
RN=C=S + 2Cl2 → 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:
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