One-pot synthesis of 4-(phenylselanyl)-substituted pyrazoles

2016-03-02
Zora, Metin
KIVRAK, Arif
Kelgokmen, YILMAZ
A facile, one-pot, general synthetic method for the preparation of 4-(phenylselanyl)pyrazoles is described. When reacted with hydrazines, alpha,beta-alkynic aldehydes produced in situ alpha,beta-alkynic hydrazones, which, upon treatment with phenylselenyl chloride, undergo cyclization to afford 4-(phenylselanyl)pyrazoles in good to high yields. This cyclization has been found to be general for a variety of in situ generated alpha,beta-alkynic hydrazones and exhibits good tolerance to a broad range of substituents, including electron-donating and electron-withdrawing groups. The enrichment of the pyrazole core with a selenyl moiety as well as with aryl and/or ferrocenyl groups may offer potential for the synthesis of molecules with pronounced or distinct biological activities.
TETRAHEDRON LETTERS

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Citation Formats
M. Zora, A. KIVRAK, and Y. Kelgokmen, “One-pot synthesis of 4-(phenylselanyl)-substituted pyrazoles,” TETRAHEDRON LETTERS, pp. 993–997, 2016, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/42758.