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Abstract Photomediated Atom Transfer Radical Polymerization (photoATRP) is an activator regeneration method, which allows for the controlled synthesis of well‐defined polymers via light irradiation. Traditional photoATRP is often limited by the need for high‐energy ultraviolet or violet light. These could negatively affect the control and selectivity of the polymerization, promote side reactions, and may not be applicable to biologically relevant systems. This drawback can be circumvented by an introduction of the catalytic amount of photocatalysts, which absorb visible and/or NIR light and, therefore, controlled, regenerative ATRP can be performed with the dual‐catalytic cycle. Herein, a critical summary of recent developments in the field of dual‐catalysis concerning Cu‐catalyzed ATRP is provided. Contributions of involved species are examined mechanistically, followed by challenges and future directions towards the next generation of advanced functional macromolecular materials. 

Abstract Atom transfer radical polymerization (ATRP) of oligo(ethylene oxide) monomethyl ether methacrylate (OEOMA₅₀₀) in water is enabled using CuBr₂with tris(2‐pyridylmethyl)amine (TPMA) as a ligand under blue or green‐light irradiation without requiring any additional reagent, such as a photo‐reductant, or the need for prior deoxygenation. Polymers with low dispersity (Đ = 1.18–1.25) are synthesized at high conversion (>95%) using TPMA from three different suppliers, while no polymerization occurred with TPMA is synthesized and purified in the laboratory. Based on spectroscopic studies, it is proposed that TPMA impurities (i.e., imine and nitrone dipyridine), which absorb blue and green light, can act as photosensitive co‐catalyst(s) in a light region where neither pure TPMA nor [(TPMA)CuBr]⁺absorbs light. 

Abstract Simple synthetic routes to regioselectively deuterated tris[2‐(dimethylamino)ethyl]amine (Me₆TREN) variants are described. Imine formation with formaldehyde‐d₂from tris(2‐aminoethyl)amine (TREN) and subsequent reductions with NaBD₄afforded N[CH₂CH₂N(CD₃)₂]₃ord₁₈‐Me₆TREN in 79 % yield. A trisubstitution protocol from 2‐bromo‐N,N‐dimethylacetamide and ammonium carbonate and subsequent reduction of the N(CH₂CONMe₂)₃intermediate by lithium aluminum deuteride has afforded N[CH₂CD₂N(CH₃)₂]₃or (d₆‐arm)‐Me₆TREN in three steps and 52 % overall yield. A similar protocol from 2‐bromo‐N,N‐dimethyl‐d₂‐acetamide, obtained in two steps fromd₄‐acetic acid, with reduction of the N(CD₂CONMe₂)₃intermediate by lithium aluminum hydride has afforded N[CD₂CH₂N(CH₃)₂]₃or (d₆‐cap)‐Me₆TREN in four steps and 13 % overall yield from CD₃COOD.