Stereoselective synthesis of spirocyclopentanones via N-heterocyclic carbene-catalyzed reactions of enals and dienones.
نویسندگان
چکیده
Homoenolates generated from enals by nucleophilic heterocyclic carbene (NHC) catalysis undergo a conjugate addition/cyclization sequence with cyclic dienones, culminating in the efficient synthesis of spirocyclopentanones.
منابع مشابه
Understanding the mechanism of stereoselective synthesis of cyclopentenes via N-heterocyclic carbene catalyzed reactions of enals with enones.
The N-heterocyclic carbene (NHC) catalyzed addition of enals to enones to yield trans-cyclopentenes has been investigated using DFT methods at B3LYP/6-31G** computational level. This NHC catalyzed reaction comprises several steps. The first one is the formation of a Breslow intermediate, which nucleophilically attacks to the conjugated position of the enone to yield an enol-enolate. This second...
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ورودعنوان ژورنال:
- Chemical communications
دوره 6 شماره
صفحات -
تاریخ انتشار 2008