We found that dichloromethane is a powerful chlorinating reagent for the congested 3 degrees and 2 degrees Csp(3)-Br bond of alpha-bromocarbonyl amides, esters, and ketones. In the presence of an appropriate copper complex as a catalyst, the desired chlorination occurred within an hour. Control experiments revealed that in situ-generated CuCl2 is a key chlorinating agent that reacts with the 3 degrees or 2 degrees alkyl radicals generated by the reaction between an alpha-bromocarbonyl compound and a Cu(I) salt.