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Updated: Jul 6, 2025
Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Stabilization of Acenes: "Geländer"-Pentacenes
Philipp Ludwig1, Frank Rominger1, Jan Freudenberg1
1Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120, Heidelberg, Germany.
Abstract:
We report soluble tetrakis-biphenylyl substituted pentacenes comprised of sp2 carbons and synthesized from pentacene-5,7,12,14-tetraone. Intramolecular Yamamoto coupling of two tetrakis(chlorobiphenylyl)pentacenes yields helical, doubly wrapped pentacenes, in which the quaterphenylene units solubilize the pentacenes and shield their central anthracene units to an unprecedented degree. The criss-cross-bridged pentacenes resist (photo)oxidation, Diels-Alder reactions and are much less reactive than TIPS-ethynylated pentacene. Extension of this concept might provide access to the larger acenes.
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