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Updated: Jun 27, 2026

Synthesis of Cyclic Polymers and Characterization of Their Diffusive Motion in the Melt State at the Single Molecule Level
Published on: September 26, 2016
Double homologation method for substituted soluble pentacenes and dimerization behaviours of pentacenes
Shi Li1, Zhiping Li, Kiyohiko Nakajima
1Catalysis Research Center, Hokkaido University, and SORST, Japan Science and Technology Agency (JST), Kita 21, Nishi 10, Kita-ku, Sapporo 001-0021, Japan.
Abstract:
Double up: A zirconium-mediated double homologation method was successfully applied for the synthesis of multi-substituted pentacene derivatives from 1,2,4,5-tetrakis(propargyl)benzenes. The bis(zirconacyclopentadiene) intermediates were also characterized. Among these symmetrical derivatives, tetra- and octa-substituted pentacenes undergo reversible conversion between monomeric and dimeric forms. A double homologation method for the formation of substituted soluble pentacenes was developed by a zirconium-mediated cyclization of tetrayne derivatives. Thermal dimerization of tetra- and octasubstituted pentacenes was observed. The dimerization behavior was observed to be strongly related to the substituent groups affixed to the pentacenes.
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