Practical access to highly enantioenriched quaternary carbon Michael adducts using simple organocatalysts.
نویسندگان
چکیده
A three component catalyst system entailing an amino acid (O(t)Bu-L-threonine), a hydrogen bond donor (sulfamide), and an amine base (DMAP) allows α-branched aldehyde addition to nitroalkenes in good to high yield and excellent ee. Importantly, the lowest reported catalyst loading (5.0 mol%) and aldehyde stoichiometry (1.2-2.0 equiv) is demonstrated and in most instances the best current product profile is observed.
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 9 1 شماره
صفحات -
تاریخ انتشار 2011