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Updated: Jul 10, 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
Three-step synthesis of end-substituted pentacenes
Matthew T Stone1, Harry L Anderson
1Department of Chemistry, Chemistry Research Laboratory, University of Oxford, 12 Mansfield Road, Oxford OX1 3TA, U.K. matthew.stone@chem.ox.ac.uk
Abstract:
A concise, three-step synthesis of 1,4,8,11-substituted 2,3,9,10-tetrakis(methoxycarbonyl)pentacenes from commercially available 1,2,4,5-tetrakis(bromomethyl)benzene was established. Efficient alkynylation, followed by formation of four fused rings via a zirconacyclopentadiene intermediate, and then oxidation with DDQ gave pentacenes 1a-c. The process was compatible with methyl, phenyl, and trimethylsilyl substituents, which have good solubility in various organic solvents.
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