Application of 7-azaisatins in enantioselective Morita–Baylis–Hillman reaction
نویسندگان
چکیده
7-Azaisatin and 7-azaoxindole skeletons are valuable building blocks in diverse biologically active substances. Here 7-azaisatins turned out to be more efficient electrophiles than the analogous isatins in the enantioselective Morita-Baylis-Hillman (MBH) reactions with maleimides using a bifunctional tertiary amine, β-isocupreidine (β-ICD), as the catalyst. This route allows a convenient approach to access multifunctional 3-hydroxy-7-aza-2-oxindoles with high enantiopurity (up to 94% ee). Other types of activated alkenes, such as acrylates and acrolein, could also be efficiently utilized.
منابع مشابه
Bifunctional ferrocene-based squaramide-phosphine as an organocatalyst for highly enantioselective intramolecular Morita-Baylis-Hillman reaction.
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