A new strategy for the synthesis of pyridines from N-propargylic beta-enaminothiones

Date

2019-03-07

Author

Kelgokmen, Yilmaz
Zora, Metin

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A new method for the synthesis of 2,4,5-trisubstituted pyridines from N-propargylic beta-enaminothiones is reported. beta-Enaminothiones were prepared by thionation of the corresponding beta-enaminones with Lawesson's reagent. When treated with diisopropylamine in DMF at room temperature, N-propargylic beta-enaminothiones yielded 2,4,5-trisubstituted pyridines in moderate to high yields, along with small amounts of 2-methylene-2,3-dihydro-1,4-thiazepines. The reaction was found to be general for a broad range of N-propargylic beta-enaminothiones and tolerated the presence of aromatic, heteroaromatic and aliphatic groups with electron-withdrawing and electron-donating substituents. The method could be widened to the internal alkyne-tethered N-propargylic beta-enaminothiones. This operationally simple method may provide rapid access to a library of functionalized pyridines of pharmacological interest.

Subject Keywords

Physical and Theoretical Chemistry, Organic Chemistry, Biochemistry

URI

https://hdl.handle.net/11511/37437

Journal

ORGANIC & BIOMOLECULAR CHEMISTRY

DOI

https://doi.org/10.1039/c8ob03180k

Collections

Department of Chemistry, Article

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Citation Formats

Y. Kelgokmen and M. Zora, “A new strategy for the synthesis of pyridines from N-propargylic beta-enaminothiones,” ORGANIC & BIOMOLECULAR CHEMISTRY, pp. 2529–2541, 2019, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/37437.