Chemoselective transfer hydrogenation of α,β-unsaturated carbonyls catalyzed by a reusable supported Pd nanoparticles on biomass-derived carbon
作者:Tao Song、Yanan Duan、Yong Yang
DOI:10.1016/j.catcom.2018.11.017
日期:2019.2
We herein report highly chemoselective transfer hydrogenation of α,β-unsaturatedcarbonyl compounds to saturatedcarbonyls with formic acid as a hydrogen donor over a stable and recyclable heterogeneous Pd nanoparticles (NPs) on N,O-dual doped hierarchical porous biomass-derived carbon. The synergistic effect between Pd NPs and incorporated heteroatoms on carbon plays a critical role on promoting the
Chemoselective Hydrogenation of α,β-Unsaturated Carbonyls Catalyzed by Biomass-Derived Cobalt Nanoparticles in Water
作者:Tao Song、Zhiming Ma、Yong Yang
DOI:10.1002/cctc.201801987
日期:2019.2.20
selectivity for hydrogenation of C=C in α,β‐unsaturated carbonyls under mild conditions. A broad set of α,β‐aromatic and aliphatic unsaturated carbonyls were selectively reduced to their corresponding saturatedcarbonyls in up to 99 % yields with good tolerance of various functional groups. Meanwhile, a new straightforward one‐pot cascade synthesis of saturatedcarbonyls was realized with high activity and
Cascade Reaction by Chemo- and Biocatalytic Approaches to Obtain Chiral Hydroxy Ketones and <i>anti</i>
1,3-Diols
作者:Raffaella Gandolfi、Giorgio Facchetti、Michael S. Christodoulou、Marco Fusè、Fiorella Meneghetti、Isabella Rimoldi
DOI:10.1002/open.201800056
日期:2018.5
biocatalytic cascade approach was applied for the stereoselectivesynthesis of hydroxy ketones and the corresponding 1,3‐diols. A new class of tridentate N,N,O ligands was used with copper(II) complexes for the asymmetric β‐borylation of α,β‐unsaturated compounds. The complex containing ligand L5 emerged as the best performer, and it gave the organoborane derivatives with good ee values. The corresponding keto–alcohol
Catalyst-free chemoselective conjugate addition and reduction of α,β-unsaturated carbonyl compounds <i>via</i> a controllable boration/protodeboronation cascade pathway
作者:Xi Huang、Junjie Hu、Mengying Wu、Jiayi Wang、Yanqing Peng、Gonghua Song
DOI:10.1039/c7gc02863f
日期:——
addition and 1,4-reduction of α,β-unsaturatedcarbonylcompounds. Without any metal-catalyst or base, a series of β-boration products of α,β-unsaturatedcarbonylcompounds was easily obtained in moderate to excellent yields in a mixed solvent of ethanol and water. The presence of a catalytic amount of Cs2CO3 can effectively induce further protodeboronation reaction towards 1,4-reduction products at
已开发出一种新颖,有效的无过渡金属且可控制的硼酸化/原硼酸脱硼策略,用于化学选择性结合物的添加和α,β-不饱和羰基化合物的1,4-还原。在没有任何金属催化剂或碱的情况下,在乙醇和水的混合溶剂中,很容易以中等至极好的收率获得一系列α,β-不饱和羰基化合物的β-硼酸酯产物。催化量的Cs 2 CO 3的存在可以在较高的反应温度下有效地引发进一步的原硼酸脱硼反应,生成1,4-还原产物。因此,通过稍微改变反应条件,可控制地获得α,β-不饱和羰基化合物的硼酸化或还原产物。机理研究表明Cs 2CO 3在激活原去硼化步骤中起关键作用。这种无过渡金属催化剂且产物可控的方法为高化学选择性制备α,β-不饱和羰基化合物的β-硼酸酯产物和1,4-还原产物提供了有用且环保的工具。
Highly Diastereoselective Synthesis of α-Difluoromethyl Amines from N-tert-Butylsulfinyl Ketimines and Difluoromethyl Phenyl Sulfone
作者:Jun Liu、Jinbo Hu
DOI:10.1002/chem.201000893
日期:——
with an in situgenerated PhSO2CF2− anion, which provides a powerful synthetic method for the preparation of a variety of structurally diverse homochiral α‐difluoromethyl tertiary carbinamines, including α‐difluoromethyl allylic amines and α‐difluoromethyl propargylamines. The stereocontrol mode of the present diastereoselective difluoromethylation of ketimines was found to be different from that of other