The present invention suggests 2-oxo-1,3-dioxolane-4-acyl halides of formula (I), wherein X is selected from F, Cl, Br, I and mixtures thereof, preferably Cl, processes for the preparation of said 2-oxo-1,3-dioxolane-4-acyl halides, the use of said 2-oxo-1,3-dioxolane-4-acyl halides for the preparation of 2-oxo-1,3-dioxolane-4-carboxylic esters of formula (II), the use of said 2-oxo-1,3-dioxolane-4-acyl halides for the preparation of 2-oxo-1,3-dioxolane-4-carboxamides of formula (III), and also the use of said 2-oxo-1,3-dioxolane-4-acyl halides as agents for the blocking of amines.