A highly efficient asymmetric Michael addition of α,α-disubstituted aldehydes to maleimides catalyzed by primary amine thiourea salt.
نویسندگان
چکیده
The first highly efficient Michael addition of challenging α,α-disubstituted aldehydes to maleimides catalyzed by a simple bifunctional primary amine thiourea catalyst/benzoic acid system has been successfully developed to generate quaternary carbon centers in high yields (up to 99%) with excellent enantioselectivities (91-99%).
منابع مشابه
Solvent-Dependent Enantioswitching in the Michael Addition of α,α-Disubstituted Aldehydes to Maleimides Organocatalyzed by Mono-N-Boc-Protected Cyclohexa-1,2-Diamines
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 so...
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ورودعنوان ژورنال:
- Organic & biomolecular chemistry
دوره 8 20 شماره
صفحات -
تاریخ انتشار 2010