Journal of Polymer Science Part A: Polymer Chemistry, Vol.55, No.18, 3017-3027, 2017
Solvent Effects on the Intramolecular Charge Transfer Character of N,N-Diaryl Dihydrophenazine Catalysts for Organocatalyzed Atom Transfer Radical Polymerization
The nature of intramolecular charge transfer (CT) of N, N-diaryl dihydrophenazine photocatalysts (PCs) in different solvents is explored in context of their performance in organocatalyzed atom transfer radical polymerization (O-ATRP). PCs having a computationally predicted lowest energy excited state exhibiting CT character can operate a highly controlled O-ATRP in a wide range of solvent polarities, from non-polar hexanes to highly polar N, N-dimethylacetamide. For PCs having a computationally predicted lowest energy excited state not possessing CT character, their ability to operate a controlled O-ATRP is decreased. This study confirms the importance of CT character in the excited state for N, N-diaryl dihydrophenazine PCs, and a deeper understanding of the activity of CT PCs has enabled the synthesis of polymers of low dispersity (< 1.10) in a controlled fashion. (C) 2017 Wiley Periodicals, Inc.