title: A Comprehensive Study of Copper Guanidine Quinoline Complexes: Predicting the Activity of Catalysts in ATRP with DFT.
abstract: Copper complexes of the hybrid guanidine ligands 1,3-dimethyl-N-(quinolin-8-yl)-imidazolidin-2-imine (DMEGqu) and 1,1,3,3-tetramethyl-2-(quinolin-8-yl)-guanidine (TMGqu) have been studied comprehensively with regard to their structural and electrochemical properties and their activity in atom transfer radical polymerization (ATRP). A simple analysis of the molecular structures of the complexes gives no indication about their activity in ATRP; however, with the help of DFT and NBO analysis the influence of particular coordinating donors on the electrochemical properties could be fully elucidated. With an adequate DFT methodology and newly applied theoretical isodesmic reactions it was possible to predict the relative position of the redox potentials of copper complexes containing DMEGqu and TMGqu ligands. In addition, predictions could be made as to whether the complexes of DMEGqu or TMGqu are more active in ATRP. Four new Cu(I) complexes were tested in standard ATRP reactions and kinetically investigated both in bulk and in solution. It could be proven that complexes featuring DMEGqu possess a lower redox potential and are more active in ATRP, although the tetramethylguanidine moiety represents the stronger donor.
authors: Institut für Anorganische Chemie, RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany.
authors: Thomas
authors: T
authors: Rösener
authors: Technische Universität Dortmund, Fakultät CCB, Otto-Hahn-Str. 6, 44277, Dortmund, Germany.
authors: Olga
authors: O
authors: Bienemann
authors: Department für Chemie und Pharmazie, Ludwig-Maximilians Universität München, Butenandtstraße 5-13, 81377, München, Germany.
authors: Kerstin
authors: K
authors: Sigl
authors: Institut für Anorganische Chemie, RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany.
authors: Nora
authors: N
authors: Schopp
authors: Department für Chemie und Pharmazie, Ludwig-Maximilians Universität München, Butenandtstraße 5-13, 81377, München, Germany.
authors: Fabian
authors: F
authors: Schnitter
authors: Department Chemie, Universität Paderborn, Warburger Str.100, 33098, Paderborn, Germany.
authors: Ulrich
authors: U
authors: Flörke
authors: Institut für Anorganische Chemie, RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany.
authors: Alexander
authors: A
authors: Hoffmann
authors: Department Chemie, Universität Paderborn, Warburger Str.100, 33098, Paderborn, Germany.
authors: Artjom
authors: A
authors: Döring
authors: Department Chemie, Universität Paderborn, Warburger Str.100, 33098, Paderborn, Germany.
authors: Dirk
authors: D
authors: Kuckling
authors: Institut für Anorganische Chemie, RWTH Aachen University, Landoltweg 1, 52074, Aachen, Germany. sonja.herres-pawlis@ac.rwth-aachen.de.
authors: Sonja
authors: http://orcid.org/0000-0002-4354-4353
authors: S
authors: Herres-Pawlis
keywords: ATRP; copper; density functional calculations; guanidine; molecular structure