Asymmetric catalysis via dynamic substrate/ligand/rare earth metal conglomerate
Akihiro Nojiri1, Naoya Kumagai, Masakatsu Shibasaki
1Graduate School of Pharmaceutical Sciences, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, 113-0033 Tokyo, Japan.
Abstract:
A highly enantio- and diastereoselective catalytic asymmetric Mannich-type reaction of alpha-cyanoketones and N-Boc imines promoted by an amide ligand/Sc(OiPr)3 catalyst is described. The similar reaction outcome is obtained with/without precomplexation of catalyst, suggesting that reaction components in a non-ordered conglomerate mixture orchestrate to form an ordered transition state during the reaction. Spectroscopic data and Eyring plot are consistent with this assumption.
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