This work was supported by a Grant-in-Aid for Specially Promoted Research and a Grant-in-Aid for Encouragements for Young Scientists (B) (for S.M.) from JSPS and MEXT.
Non-C2-Symmetric, Chirally Economical, and Readily Tunable Linked-binols: Design and Application in a Direct Catalytic Asymmetric Mannich-Type Reaction†
Article first published online: 28 APR 2005
Copyright © 2005 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
Angewandte Chemie International Edition
Volume 44, Issue 22, pages 3470–3474, May 30, 2005
How to Cite
Yoshida, T., Morimoto, H., Kumagai, N., Matsunaga, S. and Shibasaki, M. (2005), Non-C2-Symmetric, Chirally Economical, and Readily Tunable Linked-binols: Design and Application in a Direct Catalytic Asymmetric Mannich-Type Reaction. Angew. Chem. Int. Ed., 44: 3470–3474. doi: 10.1002/anie.200500425
- Issue published online: 24 MAY 2005
- Article first published online: 28 APR 2005
- Manuscript Received: 4 FEB 2005
- amino alcohols;
- asymmetric catalysis;
- chiral ligands;
- Mannich reaction;
An achiral unit is shown to be better than a chiral unit in promoting an asymmetric reaction. Non-C2-symmetric linked-binols 1 with one chiral 1,1′-bi-2-naphthol unit and one flexible achiral unit are employed as ligands in direct catalytic asymmetric Mannich-type reactions (see scheme; TON=turnover number). With as little as 0.01 mol % of ligand 1 a and 0.04 mol % of Et2Zn, the reaction proceeded smoothly to give the product in 98 % ee.