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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
Metadata
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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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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.