The Scholl cyclization for creating seven-membered rings is of great importance in synthesizing negatively curved polycyclic aromatic compounds.In this study,we systematically report a methodical approach for converti...The Scholl cyclization for creating seven-membered rings is of great importance in synthesizing negatively curved polycyclic aromatic compounds.In this study,we systematically report a methodical approach for converting[6]helicenes into negatively curved hexa[7]circulene using Scholl cyclization.The reaction revealed that the electron-donating substituents on the helicene terminal rings of helicenes facilitate the cyclization process while electron-withdrawing substituents would impede the cyclization.This was supported by theoretical calculations on the reaction process focusing on the arenium cation pathways.Through the application of this Scholl cyclization,a series of negatively curved hexa[7]circulene derivatives were synthesized,showing highly curved and twisted geometries.Notably,2,15-substituted derivatives exhibited high conformational stability against racemization,thereby performing circularly polarized luminescence with|glum|up to 4×10^(-3).展开更多
基金financially supported by the Zhejiang Provincial Natural Science Foundation,China(No.LY23B040003)the Science Foundation of Zhejiang Sci-Tech University,China(No.22062026-Y)。
文摘The Scholl cyclization for creating seven-membered rings is of great importance in synthesizing negatively curved polycyclic aromatic compounds.In this study,we systematically report a methodical approach for converting[6]helicenes into negatively curved hexa[7]circulene using Scholl cyclization.The reaction revealed that the electron-donating substituents on the helicene terminal rings of helicenes facilitate the cyclization process while electron-withdrawing substituents would impede the cyclization.This was supported by theoretical calculations on the reaction process focusing on the arenium cation pathways.Through the application of this Scholl cyclization,a series of negatively curved hexa[7]circulene derivatives were synthesized,showing highly curved and twisted geometries.Notably,2,15-substituted derivatives exhibited high conformational stability against racemization,thereby performing circularly polarized luminescence with|glum|up to 4×10^(-3).
