title: Near-Infrared Circularly Polarized Light Triggered Enantioselective Photopolymerization by Using Upconversion Nanophosphors.
abstract: Circularly polarized light (CPL) is considered to be a true chiral entity and has been suggested as an explanation for the introduction of initial chiral biases into key biomolecular building blocks. CPL used recently asymmetric photochemical reactions is of wavelengths mainly in the UV and visible regions, whereas natural CPL observed in star-forming regions of the Orion constellation falls in the IR region. Whether CPL in the IR or near-IR region could be utilized to trigger asymmetric photochemical reactions remains to be determined. Herein, it is demonstrated that enantioselective photopolymerization can be realized by using λ=980 nm CPL as the only chiral source. By incorporating NaYF4nanophosphors as the antenna species, the enantioselective photopolymerization of achiral benzaldehyde-substituted diacetylene monomer can be realized based on an upconversion mechanism upon exposure to λ=980 nm CPL. The screw direction of the helical PDA chains can be completely controlled by the handedness of incident λ=980 nm CPL.
authors.affiliation: Department of Polymer Science and Engineering, iChEM, University of Science and Technology of China, Jinzhai Road 96th, Hefei, Anhui, 230026, P.R. China.
authors.forename: Guang
authors.initials: G
authors.lastname: Yang
authors.affiliation: Department of Optics and Optical Engineering, University of Science and Technology of China, Jinzhai Road 96th, Hefei, Anhui, 230026, P.R. China.
authors.forename: Liangfu
authors.initials: L
authors.lastname: Zhu
authors.affiliation: Department of Polymer Science and Engineering, iChEM, University of Science and Technology of China, Jinzhai Road 96th, Hefei, Anhui, 230026, P.R. China.
authors.forename: Jingang
authors.initials: J
authors.lastname: Hu
authors.affiliation: Department of Polymer Science and Engineering, iChEM, University of Science and Technology of China, Jinzhai Road 96th, Hefei, Anhui, 230026, P.R. China.
authors.forename: Hongyan
authors.initials: H
authors.lastname: Xia
authors.affiliation: Department of Optics and Optical Engineering, University of Science and Technology of China, Jinzhai Road 96th, Hefei, Anhui, 230026, P.R. China.
authors.forename: Dong
authors.initials: D
authors.lastname: Qiu
authors.affiliation: Department of Polymer Science and Engineering, iChEM, University of Science and Technology of China, Jinzhai Road 96th, Hefei, Anhui, 230026, P.R. China.
authors.forename: Qijin
authors.initials: Q
authors.lastname: Zhang
authors.affiliation: Department of Optics and Optical Engineering, University of Science and Technology of China, Jinzhai Road 96th, Hefei, Anhui, 230026, P.R. China.
authors.forename: Douguo
authors.initials: D
authors.lastname: Zhang
authors.affiliation: Department of Polymer Science and Engineering, iChEM, University of Science and Technology of China, Jinzhai Road 96th, Hefei, Anhui, 230026, P.R. China.
authors.forename: Gang
authors.initials: G
authors.lastname: Zou
keywords: chirality; circular dichroism; lanthanides; nanoparticles; polymers