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Updated: Aug 13, 2025
Accessing Valuable Ligand Supports for Transition Metals: A Modified, Intermediate Scale Preparation of 1,2,3,4,5-Pentamethylcyclopentadiene
Published on: March 20, 2017
Boron-Doped Pentacenes: Isolation of Crystalline 5,12- and 5,7-Diboratapentacene Dianions
Joshua E Barker1, Akachukwu D Obi1, Diane A Dickie1
1Department of Chemistry, University of Virginia, Charlottesville, Virginia 22904, United States.
Abstract:
The syntheses, molecular structures, reactivities, and computational assessment of dipotassium diboratapentacene isomers are described (1 and 2). These compounds represent the first examples of aromatized diboraacenes where the boron atoms are spatially separated in different rings of the acene framework. Both 1 and 2 react with carbon dioxide (CO2) via diastereoselective carboxylation of the pentacene backbone that likely proceeds by a frustrated Lewis pair-like mechanism. The placement of the boron atoms and the reactivity studies provide a platform for later stage functionalization of diboraacenes beyond the central ring of the polycyclic aromatic hydrocarbon core.
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