Xue Dong, Chen Ying-Chun, Cui Xin, Wang Qi-Wei, Zhu Jin, Deng Jin-Gen
Key Laboratory of Asymmetric Synthesis & Chirotechnology of Sichuan Province, Chengdu Institute of Organic Chemistry, Chinese Academy of Sciences, Chengdu 610041, China.
J Org Chem. 2005 Apr 29;70(9):3584-91. doi: 10.1021/jo0478205.
[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.
[反应：见正文] 研究发现，在二胺-钌配合物催化的活化α,β-不饱和酮的转移氢化反应中，化学选择性可从C=O键完全切换至C=C键。此外，这种通过金属氢化物的加成反应已应用于各种活化烯烃的还原反应。在α-或β-位C=C键上取代的官能团的吸电子能力对反应活性有很大影响。此外，研究了多种手性二胺-Ru(II)-(芳烃)体系，以探索前手性α,α-二氰基烯烃的不对称转移氢化反应。系统研究了两个参数，(i) N-磺酰化手性二胺配体的结构，其中首次报道了几种在DPEN苯环上取代的手性二胺，以及(ii) 金属前体的结构，并在β-碳处获得了高对映选择性（高达89% ee）。
