Pyramidalized double bonds containing endoperoxide linkages: Photooxygenation of dimethyl cis-3,8-dihydroheptalene-3,8-dicarboxylate

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1999-09-03

Author

Saracoglu, N
Menzek, A
Sayan, S
Salzner, U
Balcı, Metin

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Diels-Alder cyclo;addition utilizing singlet oxygen as the dienophile with dimethyl cis-3,8-dihydraheptalene-3,8-dicarboxylate (5) has been investigated, and monoaddition product 7 has been isolated. The addition of a second singlet oxygen to the cycloheptatriene unit in 7 gave syn-bis(norcaradiene) bis(endoperoxide) 4. H-1 NMR spectral studies and theoretical calculations indicate the increased pyramidalization in syn-4 compared with carbon analogue. The increased pyramidalization results from hyperconjugation between the central pi-bond and the four adjacent C-O bonds and by rehybridization at C3, C4, C5, and C6. Furthermore, the increased reactivity for syn-4, which is probably arising from further folding of the central double band, is also in agreement with theoretical calculations.

Subject Keywords

Hydrocarbons, Oxides, Chemical structure, Oxygen, Nuclear magnetic resonance spectroscopy

URI

https://hdl.handle.net/11511/57801

Journal

JOURNAL OF ORGANIC CHEMISTRY

DOI

https://doi.org/10.1021/jo990393o

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Graduate School of Natural and Applied Sciences, Article

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Citation Formats

N. Saracoglu, A. Menzek, S. Sayan, U. Salzner, and M. Balcı, “Pyramidalized double bonds containing endoperoxide linkages: Photooxygenation of dimethyl cis-3,8-dihydroheptalene-3,8-dicarboxylate,” JOURNAL OF ORGANIC CHEMISTRY, pp. 6670–6676, 1999, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/57801.