Synthesis of α‐Haloalkylcarbamoyl Halides

New difunctional synthetic building blocks of types (2) and (3) can be prepared by two methods. The reactants are (1) and N‐tert ‐butyl‐ N ‐vinylcarbamoyl chloride. (3) exists in equilibrium with (2a) , R 1 = R 2 = H, X = Cl.