Asymmetric organocatalytic sulfa-michael reactions of thioglycolate with isatin derived nitroalkenes

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2018
Sağesen, Selin
Organosulfur compounds are present in many natural products and drugs. Sulfa-Michael reaction is the prominent method to synthesize these molecules. The novel bifuctional organocatalysts developed in our research group enable sulfa-Michael reaction to ocur asymmetrically. In this thesis, biologically active isatin derived nitroalkenes were chosen as Sulfa-Michael acceptors. Addition of methyl thioglycolate to isatin derived nitroalkenes in the presence of the bifunctional organocatalysts was studied under different conditions. Solvent, temperature, catalyst loading and concentration screenings were done. Isatin derived nitroalkenes substituted from different positions were also tested in sulfa-Michael reactions under optimized conditions. Sulfa-Michael product was synthesized with 75% yield and 70% ee when 10 mol % 1-adamantyl squaramide/quinine catalyst was used. The nitro group in the structure was reduced catalytically in order to reveal the product to be utilized in further reactions.

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Citation Formats
S. Sağesen, “Asymmetric organocatalytic sulfa-michael reactions of thioglycolate with isatin derived nitroalkenes,” M.S. - Master of Science, Middle East Technical University, 2018.