Perfluoroalkanesulfonamide organocatalysts for asymmetric conjugate additions of branched aldehydes to vinyl sulfones.
نویسندگان
چکیده
Asymmetric conjugate additions of branched aldehydes to vinyl sulfones promoted by sulfonamide organocatalyst 6 or 7 have been developed, allowing facile synthesis of the corresponding adducts with all-carbon quaternary stereocenters in excellent yields with up to 95% ee.
منابع مشابه
Enantioselective organocatalytic conjugate addition of aldehydes to vinyl sulfones and vinyl phosphonates as challenging Michael acceptors.
Chiral framework: Chiral amines with pyrrolidine frameworks catalyze the enantioselective conjugate addition of a wide range of aldehydes to various vinyl sulfones and vinyl phosphonates in high yields and with enantioselectivities up to >99 % ee (see scheme). The high versatility of the Michael adducts is exemplified by various functionalizations with conservation of the optical purity.Chiral ...
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عنوان ژورنال:
- Molecules
دوره 18 12 شماره
صفحات -
تاریخ انتشار 2013