A one-pot process for the preparation of alkoxyamines conforming to formulae (I) or (II), preferably (I) 1 is disclosed. The process entails (1) reacting of an oxidizing agent (A) with a sterically hindered secondary amine of the general formula (III), 2 in a water-containing medium to form a reaction product and an aqueous phase, (2) removing of the aqueous phase, and (3) (adding to the reaction product a free-radical initiator (B) under conditions that promote the decomposition of the initiator to generate free radicals. Also disclosed is a process for polymerizing monomers, the process using the alkoxyamine prepared by the inventive process.