Asymmetric Synthesis of Spiropyrazolones by Sequential Organo- and Silver Catalysis
نویسندگان
چکیده
A stereoselective one-pot synthesis of spiropyrazolones through an organocatalytic asymmetric Michael addition and a formal Conia-ene reaction has been developed. Depending on the nitroalkene, the 5-exo-dig-cyclization could be achieved by silver-catalyzed alkyne activation or by oxidation of the intermediate enolate. The mechanistic pathways have been investigated using computational chemistry and mechanistic experiments.
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عنوان ژورنال:
دوره 55 شماره
صفحات -
تاریخ انتشار 2016