Unexpected regioselectivity observed in the bromination and epoxidation reactions of p-benzoquinone-fused norbornadiene: An experimental and computational study

Date

2017-03-23

Author

Essiz, Selcuk
Dalkilic, Erdin
Sari, Ozlem
DAŞTAN, Arif
Balcı, Metin

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The bromination reaction of p-benzoquinone-fused norbornadiene was studied at various temperatures (-78, 50, 0, 25, and 77 degrees C). At room temperature, the double bonds of the p-benzoquinone units were mainly brominated. The double bond of the norbornene unit also underwent a bromination reaction in a yield of only 2%. However, the reaction at -78 degrees C resulted in the formation of products derived from the attack of bromine on the norbornene double bond with higher charge density. In contrast to the bromination reaction, the epoxidation reaction of the same compound with m-chloroperbenzoic acid and dimethyldioxirane exclusively resulted in the formation of products derived from the addition to the double bond of norbornadiene. The regioselectivity observed was investigated and the results were supported by theoretical calculations.

Subject Keywords

Bromination, Epoxidation, Norbornadiene, 1,4-Benzoquinone, Electrophilic Addition

URI

https://hdl.handle.net/11511/56679

Journal

TETRAHEDRON

DOI

https://doi.org/10.1016/j.tet.2017.02.017

Collections

Graduate School of Natural and Applied Sciences, Article

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Citation Formats

S. Essiz, E. Dalkilic, O. Sari, A. DAŞTAN, and M. Balcı, “Unexpected regioselectivity observed in the bromination and epoxidation reactions of p-benzoquinone-fused norbornadiene: An experimental and computational study,” TETRAHEDRON, pp. 1640–1649, 2017, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/56679.