Enantioselective aza-Morita-Baylis-Hillman reactions of acrylonitrile catalyzed by palladium(II) pincer complexes having C2-symmetric chiral bis(imidazoline) ligands.
نویسندگان
چکیده
Significance: This paper describes the palladiumcatalyzed enantioselective aza-Morita–Baylis–Hillman reaction of acrylonitriles with imines. The bulky pincer ligand enabled the synthesis of enantioenriched α-methylene-β-aminonitriles in high yield. Comment: The palladium–pincer complex preferably activates acrylonitrile, even in the presence of ethyl acrylate. The palladium ketenimide is a key intermediate for the asymmetric induction. The palladium complex may promote other Lewis acid catalyzed reactions. Selected examples: catalyst (5 mol%) AgOAc (5 mol%) DABCO (5 mol%) i-PrCN, 4 Å MS, –10 °C
منابع مشابه
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ورودعنوان ژورنال:
- Angewandte Chemie
دوره 51 41 شماره
صفحات -
تاریخ انتشار 2012