Chiral guanidine-catalyzed asymmetric direct vinylogous Michael reaction of α,β-unsaturated γ-butyrolactams with alkylidene malonates.
نویسندگان
چکیده
The asymmetric direct vinylogous Michael reaction of α,β-unsaturated γ-butyrolactams with alkylidene malonates has been developed. Various 5-substituted 3-pyrrolidin-2-ones were obtained in high yields (up to 93%) with excellent stereoselectivities (up to 94% ee, 95 : 5 dr), using a novel bifunctional C(1)-symmetric guanidine organocatalyst embodied a secondary amine subunit.
منابع مشابه
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Asymmetric Michael addition of 1-acetylindolin-3-ones to β,γ-unsaturated α-ketoesters was investigated for the synthesis of chiral indolin-3-ones with two adjacent tertiary stereogenic centers. Under the catalysis of a chiral bifunctional squaramide derived from l-tert-leucine, a wide range of 1-acetylindolin-3-ones and β,γ-unsaturated α-ketoesters were well-tolerated in this transformation to ...
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عنوان ژورنال:
- Chemical communications
دوره 48 41 شماره
صفحات -
تاریخ انتشار 2012