Solvent‐Free Hydrohalogenation and Deuteriohalogenation by Ex Situ Generation of HX and DX Gas

Abstract The hydrohalogenation of olefins is one of the most straightforward methods to access alkyl halides. Despite safety hazards, using pure hydrogen halide gas remains the most atom economic way of performing hydrohalogenation reactions. In this work, we describe the solvent‐free hydro‐ and deuteriohalogenation of olefins using down to near‐stoichiometric amounts of hydrogen and deuterium halide gas. Two‐chamber reactors are employed as an enabling platform to access these reactive gases in a laboratory setting. Ex situ generation from inexpensive and readily available precursors provides on‐demand access to these gases (hydrogen chloride, deuterium chloride, hydrogen bromide, deuterium bromide, hydrogen iodide, and deuterium iodide) with precise stoichiometric control. Upon chemo‐ and regioselective conversion of the substrate, the halide products may be isolated without the need for any work‐up or purification steps making it a clean and labor‐, waste‐ and cost‐effective method.