Cyclopentadithiophene (CPDT) dimer dication: bipolaron model for quaterthiophenes
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Updated: Sep 28, 2026

Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
M Kozaki1, Y Yonezawa, K Okada
1Graduate School of Science, Osaka City University, 3-3-138 Sugimoto, Sumuyoshi-ku, Japan.
Abstract:
[structure: see text] Cyclopentadithiophene (CPDT) dimers in which both 3,3' and 4' ',3' " positions were bridged with 1,3-dioxalane, carbonyl, or dicyanovinylidene were prepared. These compounds have small HOMO-LUMO gaps (1.03-2.25 eV). The electrochemical oxidation of a dicyanovinylidene-bridged CPDT dimer gave a dication that had a quinoid-like structure.
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