Catalysis by Interlayer Anions of a Synthetic Hydrotalcite-like Mineral in a Halide Exchange between Organic Halides

Exchgangeable Cl− anions in the interlayer sites of a hydrotalcite-like mineral, Mg6Al2(OH)16Cl2·4H2O, catalyzed a halide-exchange reaction between C6H5CH2Cl and C4H9Br or C4H9I in toluene or in DMF. Thus, for example, a reaction between C6H5CH2Cl (33 mmol) and C4H9Br (195 mmol) in DMF at 343 K for 20 h gave C6H5CH2Br with a 90% yield on a C6H5CH2Cl basis.