Iridium-catalyzed highly chemoselective and efficient reduction of nitroalkenes to nitroalkanes in water
作者:Dong Xu、Yang Chen、Changmeng Liu、Jiaxi Xu、Zhanhui Yang
DOI:10.1039/d1gc01907d
日期:——
An iridium-catalyzed highly chemoselective and efficient transfer hydrogenation reduction of structurally diverse nitroalkenes was realized at very low catalyst loading (S/C = up to 10000 or 20 000), using formic acid or sodium formate as a traceless hydride donor in water. Excellent functionality tolerance is also observed. The turnover number and turnover frequency of the catalyst reach as high as
在非常低的催化剂负载量(S/C = 高达 10000 或 20 000)下,使用甲酸或甲酸钠作为水中的无痕氢化物供体,实现了铱催化的高化学选择性和高效转移氢化还原结构多样的硝基烯烃。还观察到优异的功能耐受性。催化剂的周转次数和周转频率高达18 600和19 200 h -1, 分别。不需要惰性气氛保护。硝基烯烃的反应性取决于它们的取代模式,pH 值是实现完全转化和优异化学选择性的关键因素。产品的纯化通过简单的萃取实现,无需柱层析。还原过程在 10 000 S/C 比率下轻松放大到 10 g 规模。这种绿色还原在对映选择性氢化中的潜力已经得到证实。
The highly chemoselective transfer hydrogenation of the carbon–carbon double bond of conjugated nitroalkenes by a rhodium complex
作者:Jing Xiang、Er-Xiao Sun、Chun-Xia Lian、Wei-Cheng Yuan、Jin Zhu、Qiwei Wang、Jingen Deng
DOI:10.1016/j.tet.2012.04.028
日期:2012.6
Chemoselective transfer hydrogenation of conjugatednitroalkenes catalyzed by [RhCl2Cp∗]2–diamine complex (Cp∗=η5-C5Me5) using HCOOH/Et3N (5:2) (TEAF) as a hydrogen source was realized. A variety of nitrostyrenes, β-methyl nitrostyrenes, and 3-methyl-4-nitro-5-alkenyl-isoxazoles were reduced smoothly in good to excellent yields in short reaction time. Other functional groups are inert under the reaction
Enantioselective hydrogenation of α,β-disubstituted nitroalkenes
作者:Shengkun Li、Kexuan Huang、Xumu Zhang
DOI:10.1039/c4cc03942d
日期:——
The first highly chemo- and enantioselective hydrogenation of α,β-disubstituted nitroalkenes was accomplished with rhodium/JosiPhos-J2 as a catalyst, with the yield and enantioselectivity of up to 95% and 94%, respectively. The α-chiral nitroalkanes will provide an entry to valuable chiral amphetamines which are otherwise not so easily accessed.
Aromatic nitroalkenes were reduced chemoselectively with baker's yeast to give the corresponding nitroalkanes.
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作者:M.A. Silin、V.I. Kelarev、O.G. Gracheva
DOI:10.1023/a:1012370727394
日期:——
A cyanoethylation of 2-acetyl-5-R-furans, 1-nitro-2(5-R-2-furyl)ethanes, and 2-nitro-1-(2-furyl)propane was investigated. The optimum conditions were determined for preparation of monocyanoethylated products: nitriles of 5-oxo-5-(5-R-2-furyl)pentanoic and 4-nitro-5-(5-R-2-furyl)pentanoic acids. The cyanoethylation of furyl-containing nitroethanes with excess acrylonitrile provided bisadducts, dinitriles of 4-nitro-4-(5-R-furfuryl)heptanedionic acids.