Organocatalytic Biomimetic Reduction of Conjugated Nitroalkenes
作者:Peter Schreiner、Zhiguo Zhang
DOI:10.1055/s-2007-983805
日期:2007.8
A thiourea-catalyzed biomimetic reduction of conjugatednitroalkenes has been developed. Various aromatic and aliphatic conjugatednitroalkenes can be reduced to give the respective nitroalkanes with good yields under mild conditions. This protocol is not only practical, but may also provide insight into the mechanisms of redox transformations in biological systems.
stereoselective synthesis of a variety of β-nitro-α-amino carboxylic acidsvia aza-Henry (nitro-Mannich) reaction of aldimines is disclosed, yielding either anti- or a rarely reported syn-configuration. The reaction operates directly on free glyoxylic acid and generates imine species in situ. Crystallization-controlled diastereoselectivity enables isolation of the target compounds in high enantio- and diastereomeric
Controllable Synthesis of Mesoporous Iron Oxide Nanoparticle Assemblies for Chemoselective Catalytic Reduction of Nitroarenes
作者:Ioannis T. Papadas、Stella Fountoulaki、Ioannis N. Lykakis、Gerasimos S. Armatas
DOI:10.1002/chem.201504685
日期:2016.3.18
electronics to magnetism, and catalysis. Recent efforts have targeted new nanostructured forms of Fe2O3 with high surface area‐to‐volume ratio and large pore volume. Herein, the synthesis of 3D mesoporousnetworks consisting of 4–5 nm γ‐Fe2O3 nanoparticles by a polymer‐assisted aggregating self‐assembly method is reported. Iron oxide assemblies obtained from the hybrid networks after heat treatment have
氧化铁(III)是一种低成本材料,其应用范围从电子学到磁学和催化学。最近的工作针对具有高表面积体积比和大孔体积的新型纳米结构Fe 2 O 3。在此,由4-5纳米γ -铁的三维中孔网络的合成2 ö 3报道由聚合物辅助聚集自组装方法的纳米颗粒。热处理后从混合网络中获得的氧化铁组件具有开孔结构,具有高表面积(最大167 m 2 g -1)和均匀的孔(约6.3 nm)。构成氧化铁纳米晶体可以从经历可控相变了γ-Fe 2ø 3到的α-Fe 2 ö 3和成Fe 3 ö 4不同退火条件下,同时保持三维结构和开放的孔隙。这些新的集成结构显示出高催化活性和稳定性,即使在大规模合成中,也可以选择性地将芳基和烷基硝基化合物还原为相应的芳基胺和肟。
Asymmetric Organocatalytic Sequential Reaction of Structurally Complex Cyclic Hemiacetals and Functionalized Nitro-olefins To Synthesize Diverse Heterocycles
作者:Jun-Ping Pei、Ying-Han Chen、Yan-Kai Liu
DOI:10.1021/acs.orglett.8b01386
日期:2018.6.15
Structurally complex cyclic hemiacetals bearing a racemic tetrasubstituted stereocenter have been prepared in a concise manner and were successfully used in an organocatalytic enantioselective sequence to react with functionalized nitro-olefins, providing bicyclic acetal-containing compounds as two separable epimers with excellent stereoselectivity. The reaction showed broad substrate scope, with respect
Nano-NiFe<sub>2</sub>O<sub>4</sub> as an efficient catalyst for regio- and chemoselective transfer hydrogenation of olefins/alkynes and dehydrogenation of alcohols under Pd-/Ru-free conditions
作者:Soumen Payra、Arijit Saha、Subhash Banerjee
DOI:10.1039/c6ra09659j
日期:——
Here, we have demonstrated magnetic nano-NiFe2O4 catalyzed transferhydrogenation of olefins/alkynes using isopropyl alcohol as source of hydrogen under ligand/ base/ Pd-/ Ru-metal-free conditions and dehydrogenation of alcohols under oxidant-free...