Enantioselective sulfa-Michael addition reaction of methyl thioglycolate to chalcones derivatives with sterically encumbered quinine squaramide organocatalyst

Date

2018-04-04

Author

HASILCIOĞULLARI, DENİZ
Tanyeli, Cihangir

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Asymmetric organocatalytic sulfa-Michael reactions give access to enantiomerically enriched sulfur containing adducts that can be used as valuable chiral building blocks. A variety of chalcone derivatives were allowed to react with methyl thioglycolate under optimized conditions, in the presence of a bifunctional quinine derived sterically encumbered squaramide organocatalyst, giving rise to excellent stereoselectivities, up to 99% ee. The designed catalyst system proved to be efficient even at gram scale and under milder reaction conditions.

Subject Keywords

Sulfa-Michael addition, Conjugate addition, Organocatalysis, Asymmetric synthesis, Asymmetric catalysis

URI

https://hdl.handle.net/11511/38785

Journal

TETRAHEDRON LETTERS

DOI

https://doi.org/10.1016/j.tetlet.2018.02.068

Collections

Department of Chemistry, Article

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Citation Formats

D. HASILCIOĞULLARI and C. Tanyeli, “Enantioselective sulfa-Michael addition reaction of methyl thioglycolate to chalcones derivatives with sterically encumbered quinine squaramide organocatalyst,” TETRAHEDRON LETTERS, pp. 1414–1416, 2018, Accessed: 00, 2020. [Online]. Available: https://hdl.handle.net/11511/38785.