Substituent effect on regioselectivity in the di-pi-methane rearrangement: synthesis of disubstituted benzobarrelene derivatives and their photochemistry

Date

2001-11-19

Author

Unaldi, NS
Balcı, Metin

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2,3- and 2,5-Dicyanobenzobarrelenes 5 and 6 have been synthesized and subjected to triplet-sensitized photoisomerization. 2,3-Dicyanobenzobarrelene 5 gave two di-pi -methane rearrangement products 7 and 8 and a [2 pi +2 pi] -cycloaddition product 9. However, 2,5-dicyanobenzobarrelene 6 formed a single di-Tc-methane product 13. The formation of these products is discussed in terms of the radical stabilizing effect of the substituents and the destabilizing effect on the formation of the cyclopropane ring,

Subject Keywords

Di-pi-methane rearrangement, Benzobarrelene

URI

https://hdl.handle.net/11511/57506

Journal

TETRAHEDRON LETTERS

DOI

https://doi.org/10.1016/s0040-4039(01)01770-1

Collections

Graduate School of Natural and Applied Sciences, Article

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Citation Formats

N. Unaldi and M. Balcı, “Substituent effect on regioselectivity in the di-pi-methane rearrangement: synthesis of disubstituted benzobarrelene derivatives and their photochemistry,” TETRAHEDRON LETTERS, pp. 8365–8367, 2001, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/57506.