Transfer hydrogenation of activated C=C bonds catalyzed by ruthenium amido complexes: reaction scope, limitation, and enantioselectivity.
[reaction: see text] It was found that the chemoselectivity could be completely switched from C=O to C=C bonds in the transfer hydrogenation of activated alpha,beta-unsaturated ketones catalyzed by diamine-ruthenium complex. Moreover, this addition via metal hydride had been applied to the reduction of various activated olefins. The electron-withdrawing ability of functional groups substituted on C=C bonds at the alpha- or beta-position had strong influence on the reactivity. In addition, a wide variety of chiral diamine-Ru(II)-(arene) systems was investigated to explore the asymmetric transfer hydrogenation of prochiral alpha,alpha-dicyanoolefins. Two parameters had been systematically studied, (i) the structure of the N-sulfonylated chiral diamine ligands, in which several chiral diamines substituted on the benzene ring of DPEN were first reported, and (ii) the structure of the metal precursors, and high enantioselectivitiy (up to 89% ee) at the beta-carbon was obtained.
Xue
Dong
D
Key Laboratory of Asymmetric Synthesis & Chirotechnology of Sichuan Province, Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, China.
Chen
Ying-Chun
YC
Cui
Xin
X
Wang
Qi-Wei
QW
Zhu
Jin
J
Deng
Jin-Gen
JG