KO(t)Bu-Initiated Aryl C-H Iodination: A Powerful Tool for the Synthesis of High Electron Affinity Compounds
Qinqin Shi1, Siyuan Zhang2, Junxiang Zhang2
1Department of Chemistry, Emory University , Atlanta, Georgia 30322, United States.
Abstract:
An efficient iodination reaction of electron-deficient heterocycles is described. The reaction utilizes KO(t)Bu as an initiator and likely proceeds by a radical anion propagation mechanism. This new methodology is particularly effective for functionalization of building blocks for electron transport materials. Its utility is demonstrated with the synthesis of a new perylenediimide-thiazole non-fullerene acceptor capable of delivering a power conversion efficiency of 4.5% in a bulk-heterojunction organic solar cell.
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