Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
1307367 | Inorganica Chimica Acta | 2008 | 4 Pages |
Modular sugar phosphite-oxazoline L1–L5a–c and phosphite-phosphoroamidite L6a–c ligand libraries were screened in the asymmetric Ni-catalyzed 1,2-addition reactions to aldehydes. Systematically varying the electronic and steric properties of the oxazoline and biaryl phosphite substituents and the functional groups attached to the basic sugar-backbone, we found a strong influence of the oxazoline and the functional groups of the sugar-backbone on the catalytic performance. Enantioselectivity (ee values up to 59%) was best with the catalysts precursor containing the phosphite-oxazoline ligand L3a, that contains a sterically hindered tert-butyl oxazoline group.
Graphical abstractModular sugar phosphite-oxazoline and phosphite-phosphoroamidite ligand libraries were screened in the asymmetric Ni-catalyzed 1,2-addition reactions to aldehydes. Systematically varying the electronic and steric properties of the oxazoline and biaryl phosphite substituents and the functional groups attached to the basic sugar-backbone, we found a strong influence of the oxazoline and the functional groups of the sugar backbone on the catalytic performance.Figure optionsDownload full-size imageDownload as PowerPoint slide