The very high reactivity of aminoalkyl radicals toward the halogen abstraction reaction is reported for the first time. Reaction rate constants with CCl4 and CBr4 are close to the diffusion limit: they are about 4-5 orders of magnitude higher than those previously determined for typical alkyl radicals. A better understanding of this unusual behavior is obtained using molecular orbitals (MO) calculations. The participation of polar effects is directly evidenced. This approach can be useful for the design of new reducing agents. (c) 2008 Elsevier B. V. All rights reserved.