Premium
A New Sterically Highly Hindered 7‐Membered Cyclic Nitroxide for the Controlled Living Radical Polymerization
Author(s) -
Chang CheChien,
Siegenthaler Kai Oliver,
Studer Armido
Publication year - 2006
Publication title -
helvetica chimica acta
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.74
H-Index - 82
eISSN - 1522-2675
pISSN - 0018-019X
DOI - 10.1002/hlca.200690206
Subject(s) - chemistry , nitroxide mediated radical polymerization , steric effects , homolysis , moiety , polymerization , radical polymerization , polymer chemistry , styrene , acrylate , radical , photochemistry , polymer , organic chemistry , copolymer
The synthesis of a new sterically highly hindered 7‐membered alkoxyamine, 2,2,7,7‐tetraethyl‐1‐(1‐phenylethoxy)‐1,4‐diazepan‐5‐one ( 4 ), starting from known 2,2,6,6‐tetraethyl‐1‐(1‐phenylethoxy)piperidin‐4‐one ( 3 ) via a Beckmann ‐type rearrangement is presented. It is shown that ring‐enlargement by insertion of an NH moiety in going from 3 to 4 leads to a more efficient regulator for nitroxide‐mediated controlled living radical styrene (= ethenylbenzene) and butyl acrylate (= butyl prop‐2‐enoate) polymerization. In addition to the polymerization experiments, kinetic data on the reversible CO bond homolysis of alkoxyamines 3 and 4 are presented.