A new approach for the synthesis of spiro and gem-dimethyl-substituted 1,4-oxazepines from N-propargylic beta-enaminones

Date

2020-11-01

Author

Karadeniz, Eda
Kelgökmen, Yılmaz
Zora, Metin

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An efficient and general method for the synthesis of spiro-1,4-oxazepines and 3,3-dimethyl-1,4-oxazepines is reported. When treated with ZnI2 and AgSbF6 in refluxing DCE, cyclohexane-embedded N-propargylic beta-enaminones underwent 7-exo-dig cyclization to afford spiro-1,4-oxazepines, specifically 12-methylene-11-oxa-7-azaspiro[5.6]dodeca-7,9-dienes, in good to high yields. Accordingly, N-(1,1-dimethyl)propargylic beta-enaminones produced 3,3-dimethyl-1,4-oxazepines. Cyclization was found to be general for a diverse range of N-propargylic beta-enaminones with high efficiency and broad functional group tolerance. This operationally easy method might provide quick access to a library of functionalized spiro and gem-dimethyl-substituted 1,4-oxazepine derivatives of pharmacological interest.

Subject Keywords

Organic Chemistry

URI

https://hdl.handle.net/11511/69517

Journal

JOURNAL OF HETEROCYCLIC CHEMISTRY

DOI

https://doi.org/10.1002/jhet.4183

Collections

Department of Chemistry, Article

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Citation Formats

E. Karadeniz, Y. Kelgökmen, and M. Zora, “A new approach for the synthesis of spiro and gem-dimethyl-substituted 1,4-oxazepines from N-propargylic beta-enaminones,” JOURNAL OF HETEROCYCLIC CHEMISTRY, pp. 0–0, 2020, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/69517.