通过将已知使苄胺外消旋的碱与镍 (II) 盐结合,获得了活性镍纳米颗粒,可用作脂肪族和苄基伯胺外消旋化的催化剂。纳米粒子在离子液体四丁基溴化铵中稳定,可以在几小时内以优异的选择性完成大多数外消旋化。通过使用具有双相外消旋步骤的两锅系统克服了强还原性外消旋化催化剂和酶促胺拆分催化剂的不相容性问题。含有胺的壬烷层与酰化酶和离子液体中的外消旋 Ni 纳米颗粒的连续接触允许成功超过动力学拆分的 50% 酰胺产率极限。
general and efficient protocol for iso‐selective aminocarbonylation of olefins with aliphatic amines has been developed for the first time. Key to the success for this process is the use of a specific 2‐phosphino‐substituted pyrrole ligand in the presence of PdX2 (X=halide) as a pre‐catalyst. Bulk industrial and functionalized olefins react with various aliphatic amines, including amino‐acid derivatives
benzylamine, N-benzylformamide was obtained in 77% yield. 1-Octene was hydroamidated with benzylamine to N-benzylnonanamide in 67% yield (the selectivity to its linear isomer was 81%). These reactions appear to include ruthenium carbamoyl complex as the common key intermediate.
十二碳三钌(Ru 3(CO)12)是一种有效的均相催化剂前体,用于在一氧化碳压力为40 kg cm -2的条件下在120–180°C下进行胺的羰基化和烯烃的加氢酰胺化。通过苄胺的羰基化,以77%的产率获得了N-苄基甲酰胺。用苄胺将1-辛烯加氢酰胺化为N-苄基壬酰胺,产率为67%(其线性异构体的选择性为81%)。这些反应似乎包括钌氨基甲酰基络合物作为常见的关键中间体。
Nickel Nanoparticles as Racemization Catalysts for Primary Amines
作者:Inge Geukens、Eva Plessers、Jin Won Seo、Dirk E. De Vos
DOI:10.1002/ejic.201300074
日期:2013.5.6
By combining bases that are known to racemize benzylic amines with a nickel(II) salt, active nickelnanoparticles were obtained that can be used as catalysts in the racemization of both aliphatic and benzylic primaryamines. The nanoparticles are stable in the ionic liquid tetrabutylammonium bromide and can complete most racemizations within a few hours with excellent selectivity. The problem of the
通过将已知使苄胺外消旋的碱与镍 (II) 盐结合,获得了活性镍纳米颗粒,可用作脂肪族和苄基伯胺外消旋化的催化剂。纳米粒子在离子液体四丁基溴化铵中稳定,可以在几小时内以优异的选择性完成大多数外消旋化。通过使用具有双相外消旋步骤的两锅系统克服了强还原性外消旋化催化剂和酶促胺拆分催化剂的不相容性问题。含有胺的壬烷层与酰化酶和离子液体中的外消旋 Ni 纳米颗粒的连续接触允许成功超过动力学拆分的 50% 酰胺产率极限。
Synthesis and chemoselective ligations of MIDA acylboronates with O-Me hydroxylamines
作者:Hidetoshi Noda、Jeffrey W. Bode
DOI:10.1039/c4sc00971a
日期:——
N-Methyliminodiacetyl (MIDA) acylboronates undergo chemoselective amide-bond forming ligations in water with O-Me hydroxylamines, including unprotected peptide substrates. These bench-stable boronates were easily prepared from potassium acyltrifluoroborates (KATs) in one step. The reactivity of MIDA acylboronates with O-alkylhydroxylamines – which are unreactive with KATs – was attributed to the nature