期刊
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
卷 136, 期 26, 页码 9377-9384出版社
AMER CHEMICAL SOC
DOI: 10.1021/ja503060e
关键词
-
资金
- Catalysis Research Center, Hokkaido University [11A0003, 12A0001]
- MEXT, Japan
- Grants-in-Aid for Scientific Research [25620051, 26105702, 26620074, 24550121, 13J02743] Funding Source: KAKEN
The NMR and X-ray crystallographic studies clarified that planar-chiral alkenylene-bridged (phosphino-pi-arene)-(phosphine)chromium complexes 3 were capable of coordinating to a rhodium(I) cation in a bidentate fashion at the (pi-arene)-bound phosphorus atom and at the olefin moiety. The P-olefin chelate coordination of 3 constructs the effective chiral environment at the metal center, and thus, these rhodium complexes display high performances in various rhodium-catalyzed asymmetric 1,4- and 1,2-addition reactions with arylboron nucleophiles. The control experiments demonstrated that the (eta(2)-olefin) Rh interaction as well as the bridging structure in 3 played the pivotal roles in the high enantioselectivity of the Rh-catalyzed asymmetric reactions. To enhance ligands, an enantiospecific and scalable synthetic method was developed. The novel synthetic method is flexible in terms of the substituent variation, and a library of the planar-chiral (arene)chromium-based phosphine olefin ligands was established by the combinatorial approach. Among the newly prepared ligand library, compound 3g, which is with a bis(3,5-dimethylphenyl)-phosplaino group on the eta(6)-arene ring, was found to be a far better chiral ligand in the rhodium-catalyzed asymmetric reactions showing excellent enantioselectivity and high yields.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据