On October 18, 2002, Huttenloch, Oliver; Laxman, Eltepu; Waldmann, Herbert published an article.Electric Literature of 227940-70-7 The title of the article was Solid-phase development of chiral phosphoramidite ligands for enantioselective conjugate addition reactions. And the article contained the following:
The development of a method for the optimization of chiral ligands for the steric steering of enantioselective Cu-catalyzed conjugate additions of Zn-alkyls to enones is described. The method is based on combinatorial principles and solid-phase techniques. It includes the combinatorial synthesis of chiral bispidine-derived ligands embodying a phosphoramidite group on the solid phase and their study in immobilized form in the conjugate addition of ZnEt2 to cyclohexenone as test reaction. The best identified ligands were also synthesized sep. and studied in its soluble form. The results obtained for the polymer-bound ligands correctly mirrored the performance of the soluble ligands. The library embodied members giving ee values varying between 3 and 67%. The positional scanning approach proved to be invalid for the study of the ligand system, indicating that this approach in general should be applied with care. Taken together, the method allowed for rapid and efficient optimization of the ligands and led to the development of the 1st enantioselective, Cu-catalyzed conjugate addition reaction with a polymer-bound ligand. The experimental process involved the reaction of tert-Butyl 7-benzyl-9-oxo-3,7-diazabicyclo[3.3.1]nonane-3-carboxylate(cas: 227940-70-7).Electric Literature of 227940-70-7
The Article related to copper catalyzed conjugate addition diethylzinc cyclohexenone chiral phosphoramidite ligand, phosphoramidite ligand preparation combinatorial chem catalyst conjugate addition diethylzinc and other aspects.Electric Literature of 227940-70-7
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