Solvent-Dependent Enantioswitching in the Michael Addition of α,α-Disubstituted Aldehydes to Maleimides Organocatalyzed by Mono-N-Boc-Protected Cyclohexa-1,2-Diamines
نویسندگان
چکیده
Enantiomerically pure mono-N-Boc-protected trans-cyclohexane-1,2-diamines are used as organocatalysts for the enantioselective conjugate addition of α,α-disubstituted aldehydes to maleimides. Using a single enantiomer of the organocatalyst, both enantiomeric forms of the resulting Michael adducts bearing a new quaternary stereocenter are obtained in high yields, only by changing the reaction solvent from chloroform (up to 86% ee) to aqueous DMF (up to 84% ee).
منابع مشابه
Asymmetric Conjugate Addition of α,α-Disubstituted Aldehydes to Nitroalkenes Organocatalyzed by Chiral Monosalicylamides from trans-Cyclohexane-1,2-Diamines.
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