Exploiting C3-symmetry in the dynamic coordination of a chiral trisoxazoline to copper(II): improved enantioselectivity, and catalyst stability in asymmetric lewis acid catalysis.
نویسندگان
چکیده
Chiral C3-symmetric trisoxazolines are highly efficient stereodirecting ligands in enantioselective Cu(II) Lewis acid catalysis which is based on the concept of a stereoelectronic hemilability of the divalent copper; in direct comparison with the analogous bisoxazoline systems they are more efficient in the enantioselective alpha-amination as well as the enantioselective Mannich reaction of prochiral beta-ketoesters.
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ورودعنوان ژورنال:
- Chemical communications
دوره 40 شماره
صفحات -
تاریخ انتشار 2005