N-Heterocyclic carbene-catalyzed chemoselective cross-aza-benzoin reaction of enals with isatin-derived ketimines: access to chiral quaternary aminooxindoles.
نویسندگان
چکیده
A chemo- and enantioselective cross-aza-benzoin reaction between enals and isatin-derived ketimines is disclosed. The high chemoselectivity (of the acyl anion reaction over enal α- and β-carbon reactions) is enabled by the electronic and steric properties of the N-heterocyclic carbene organocatalyst.
منابع مشابه
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Hydroacylation reactions and aza-benzoin reactions have attracted considerable attention from experimental chemists. Recently, Wang et al. reported an interesting reaction of N-heterocyclic carbene (NHC)-catalyzed addition of aldehyde to enamide, in which both hydroacylation and aza-benzoin reactions may be involved. Thus, understanding the competing relationship between them is of great intere...
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ورودعنوان ژورنال:
- Organic letters
دوره 16 12 شماره
صفحات -
تاریخ انتشار 2014