Catalytic enantioselective addition of isocyanoacetate to 3-methyl-4-nitro-5-styrylisoxazoles under phase transfer catalysis conditions.
نویسندگان
چکیده
The reaction between 3-methyl-4-nitro-5-styrylisoxazoles and ethyl isocyanoacetate proceeded under phase transfer catalysis to give enantioenriched monoadducts in high enantiomeric excess (up to 99% ee). The resulting adducts were subsequently cyclised to give 2,3-dihydropyrroles and substituted pyrrolidines in identical high ees and as a single diastereoisomer.
منابع مشابه
An improved procedure to prepare 3-methyl-4-nitroalkylenethylisoxazoles and their reaction under catalytic enantioselective Michael addition with nitromethane.
Herein, we describe a short synthesis of 3-methyl-4-nitro-5-alkylethenyl isoxazoles and their reactivity as Michael acceptors. The title compounds reacted with nitromethane under phase-transfer catalysis to provide highly enantioenriched adducts (up to 93% ee) which were then converted to the corresponding γ-nitroacids.
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 13 43 شماره
صفحات -
تاریخ انتشار 2015