Low and high temperature bromination of exocyclic dienes: high temperature bromination. Part 16

Date

2003-05-19

Author

Horasan, N
Kara, Y
Azizoglu, A
Balcı, Metin

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The electrophilic addition of bromine to an exocyclic diene, 5,6-dimethylenebicyclo[2.2.1]hept-2-ene, in CCl4 at 0degreesC led to the formation of non-rearranged (73%) and rearranged products (27%). However, high temperature bromination of the exocyclic diene at 77degreesC suppressed the formation of the rearranged products. Similarly, bromination of 9,10-dimethylenetricyclo[6.2.1.0(2.7)]undeca-2,4,6-triene at -10degreesC gave only the exo-1,2-addition product. Bromination at +5degreesC resulted in the formation of a mixture consisting of exo-1,2- and 1,4-addition products in a ratio of (1:4). High temperature bromination at 77degreesC resulted in the formation of the endo-1,2-addition product. Furthermore, it has been shown that the 1,4-addition product converts smoothly to the 1,2-addition product. The formation mechanism of the products is discussed and supported by calculations.

Subject Keywords

Organic Chemistry, Biochemistry, Drug Discovery

URI

https://hdl.handle.net/11511/57812

Journal

TETRAHEDRON

DOI

https://doi.org/10.1016/s0040-4020(03)00549-0

Collections

Graduate School of Natural and Applied Sciences, Article

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Citation Formats

N. Horasan, Y. Kara, A. Azizoglu, and M. Balcı, “Low and high temperature bromination of exocyclic dienes: high temperature bromination. Part 16,” TETRAHEDRON, pp. 3691–3699, 2003, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/57812.