Rhodium‐Catalyzed Asymmetric Synthesis of β‐Branched Amides
作者:Zhao Wu、Joshua D. Laffoon、Trang T. Nguyen、Jacob D. McAlpin、Kami L. Hull
DOI:10.1002/anie.201610500
日期:2017.1.24
synthesis of chiral β‐branched amides is reported through the highly enantioselective isomerization of allylamines, followed by enamine exchange, and subsequent oxidation. The enamine exchange allows for a rapid and modular synthesis of various amides, including challenging β‐diaryl and β‐cyclic.
Phosphorus oxychloride as an efficient coupling reagent for the synthesis of esters, amides and peptides under mild conditions
作者:Hu Chen、Xunfu Xu、Liu Leo Liu、Guo Tang、Yufen Zhao
DOI:10.1039/c3ra42887g
日期:——
A mild method is described for the conversion of carboxylic acids into esters, amides, as well as peptides without racemization through carboxyl activation by the reagent combination of POCl3 and DMAP. Long chain alcohols could be converted to the corresponding ester in good yields. 31P NMR spectrum was used to detect phosphorus-containing intermediates in ongoing reactions directly, and a possible
描述了一种温和的方法,可通过POCl 3和地图。长链醇可以良好的产率转化为相应的酯。31 P NMR光谱用于直接检测正在进行的反应中的含磷中间体,并基于这些结果提出了可能的机理。
Organic ligand-free carbonylation reactions with unsupported bulk Pd as catalyst
作者:Shujuan Liu、Hongli Wang、Xingchao Dai、Feng Shi
DOI:10.1039/c8gc00740c
日期:——
ligand-free conditions, namely, hydroaminocarbonylation of olefins, aminocarbonylation of aryliodides and oxidative carbonylation of amines, which almost cover all the known mechanisms in carbonylation reactions. Notably, the bulk Pdcatalyst system exhibited better catalytic activity than the classical homogeneous PdCl2/(2-OMePh)3P catalyst system. This study will create a momentous and new field of green
oxidative C–H bond amidation of anilides with dibenzenesulfonimides mediated by PhI(OAc)2 under metal-free conditions provided para-amidated anilides with high selectivity and moderate to good yields. The reaction proceeded under mild or neutral conditions and it has good air and moisture tolerance. The method represents a novel and facile strategy for the synthesis of arylamines.
A new lipase, Ndbn, capable of efficiently catalyzing the amidation between esters and aromatic amines which are weak nucleophilic reagents was discovered. Furthermore, Ndbn exhibits the capability to catalyze the aminolysis of carboxylic acids without the need for preparing ester substrate or a strictly anhydrous reaction environment. Additionally, an unusual preference of Ndbn for aromatic amines