School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, PR China.
Org Biomol Chem. 2011 Mar 21;9(6):1871-5. doi: 10.1039/c0ob00915f. Epub 2011 Jan 31.
Palladium-catalyzed asymmetric allylic alkylation of ketones, via enamines generated in situ as nucleophiles, were carried out smoothly with chiral metallocene-based P,N-ligands. Under the same conditions, however, reactions of aldehydes could hardly be observed. Subsequently, this obstacle was resolved by using chiral metallocene-based P,P-ligands. Both ketones and aldehydes afforded excellent enantioselectivities with up to 98% ee and 94% ee, respectively.
手性茂金属 P,N-配体催化酮的烯丙基不对称烷基化反应，通过原位生成的烯胺作为亲核试剂，反应可以顺利进行。然而，在相同条件下，醛的反应几乎观察不到。随后，通过使用手性茂金属 P,P-配体解决了这一障碍。酮和醛都以高达 98%的对映选择性和 94%的对映选择性得到了极好的结果。
