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Updated: Dec 30, 2025

Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
Synthesis, Characterization and Electronic Structure of Dirhenadehyro[12]annulene Complexes
Shaohui Zheng1, Zhenwei Chu1, Ka-Ho Lee2
1Department of Materials Science and Engineering College of Materials, Xiamen University, Xiamen, 361005, P. R. China.
Abstract:
Treatment of the SiMe3 -protected dichloro-rhenium carbyne complexes Re{≡CCH=C(R)C≡CSiMe3 }Cl2 (PMe2 Ph)3 (R = CMe3 , 1-adamantyl) with CsF in methanol directly afforded the 12-membered metallacycles {ReCl(PMe2 Ph)3 }2 {≡CCH=C(R)C≡C-}2 . The electronic structure of the metallacycle was investigated by density functional calculations. The UV-vis spectrum of the metallacycle shows a red-shifted band compared to that of the starting dichlorocarbyne complex. Treatment of {ReCl(PMe2 Ph)3 }2 {≡CCH=C(CMe3 )C≡C-}2 with HCl produced the dichloro-rhenium carbyne complex Re{≡CCH=C(CMe3 )C≡CH}Cl2 (PMe2 Ph)3 , which is consistent with the electronic structure of the 12-membered metallacycles.
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