A new antiaromatic compound: 1,4-biphenylenequinone synthesis and trapping reactions: can a quinone unit stabilize the cyclobutadiene?

Date

2001-12-03

Author

Kilic, H
Balcı, Metin

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The photooxygenation of 4a,8b-dihydrobiphenylene affords an endoperoxide. NEt3-catalyzed rearrangement of this endoperoxide gave the corresponding hydroxy enone, while the CoTPP-catalyzed rearrangement afforded a bisepoxide. MnO2 oxidation of hydroxy enol leads to 4a,8b-dihydrobiphenylene-1,4-dione. The NIBS bromination of this dione produces mono- and dibromides. NEt3-supported elimination of monobromide and zinc elimination of dibromide afforded the target compound, 1,4-biphenylenequinone, which was trapped as the dimer and cycloadducts with cyclopentadiene and anthracene, respectively. Furthermore, 1,4-biphenylenequinone was generated upon oxidation of biphenylene-1,4-diol with bis(trifluoroacetoxy)iodobenzene (PIFA). The stability and reactivity of the title compound is discussed. (C) 2001 Elsevier Science Ltd. Ail rights reserved

Subject Keywords

Biphenylenequinone, Cyclobutadiene, Singlet oxygen, Diels-Alder reactions, nucleus-independent chemical shifts values

URI

https://hdl.handle.net/11511/52117

Journal

TETRAHEDRON

DOI

https://doi.org/10.1016/s0040-4020(01)01008-0

Collections

Graduate School of Natural and Applied Sciences, Article

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Citation Formats

H. Kilic and M. Balcı, “A new antiaromatic compound: 1,4-biphenylenequinone synthesis and trapping reactions: can a quinone unit stabilize the cyclobutadiene?,” TETRAHEDRON, pp. 9889–9897, 2001, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/52117.