Process for the synthesis for alkoxy amines and their use in controlled radical polymerization

A one-pot process for the preparation of alkoxyamines conforming to formulae (I) or (II)

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• wherein
• R1, R2, R3 are independently selected from the group consisting of:
• hydrogen, C1-C20alkyl, C1-C20cycloalkyl, C6-C24aryl, halogen, cyano, hydroxy, amino, C1-C20alkylester C1-C20cycloalkylester, C1-C20alkylamide, C1-C20cycloalkylamide C6-C24-arylester and C6-C24-arylamide;
• or
• R1, R2, R3 form, together with the carbon atom linking them, a C3-C12cycloalkyl radical, a (C4-C12alkanol)yl radical or a C2-C13-heterocycloalkyl radical containing oxygen, sulfur or nitrogen atoms;
• R4 and R5 are independently selected from the group consisting of C1-C18alkyl, C2-C18alkenyl, C2-C18alkynyl, C3-C12cycloalkyl, C3-C12heterocycloalkyl and C6-C24-aryl, all of which are optionally substituted by NO2, halogen, amino, hydroxy, cyano, carboxy, ketone, C1-C4alkoxy, C1-C4alkylthio, C1-C4alkylamino, dialkyl phosphonates;
• or
• R4 and R5 form, together with the nitrogen atom linking them, a C3-C12cycloalkyl radical, a (C4-C12alkanol)yl radical or a C2-C13-heterocycloalkyl radical containing oxygen, sulfur or nitrogen atoms;
• or
• R4 and R5 together form a residue of a polycyclic ring system or a polycyclic heterocycloaliphatic ring system containing oxygen, sulfur or nitrogen atoms;
• wherein the carbon atom of the R4 and R5 radicals directly adjacent to the alkoxyamine nitrogen atom is in each case substituted by 3 further organic substituents;
• comprising the reaction steps of
• (1) reacting of an oxidizing agent (A) with a sterically hindered secondary amine of the general formula (III),
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• in a water-containing medium to form a reaction product and an aqueous phase,
• (2) removing of the aqueous phase,
• (3) adding to the reaction product a free-radical initiator (B) under conditions that promote the decomposition of the initiator to generate radicals of the general formulae (IV) or (V):
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