Selective Construction of C−C and C=C Bonds by Manganese Catalyzed Coupling of Alcohols with Phosphorus Ylides
作者:Xin Liu、Thomas Werner
DOI:10.1002/adsc.202001209
日期:2021.2.16
manganese catalyzed coupling of alcohols with phosphorus ylides. The selectivity in the coupling of primary alcohols with phosphorus ylides to form carbon‐carbon single (C−C) and carbon‐carbon double (C=C) bonds can be controlled by the ligands. In the conversion of more challenging secondary alcohols with phosphorus ylides the selectivity towards the formation of C−C vs. C=C bonds can be controlled by the
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。
Mechanistic studies of DCC/HOBt-mediated reaction of 3-phenylpropionic acid with benzyl alcohol and studies on the reactivities of ‘active ester’ and the related derivatives with nucleophiles
extensive study for peptide synthesis, DCC-mediated esterification is left still unclear. Therefore, DCC- and DCC/HOBt-mediated reactions of 3-phenylpropionic acid (1) with benzyl alcohol were carried out under several mechanistic considerations. Further, in order to determine the reactivities of the so-called ‘active esters’ compounds changing the substituents bearing carbonyl and relatedderivatives group
Nickel-Catalyzed Esterification of Aliphatic Amides
作者:Liana Hie、Emma L. Baker、Sarah M. Anthony、Jean-Nicolas Desrosiers、Chris Senanayake、Neil K. Garg
DOI:10.1002/anie.201607856
日期:2016.11.21
demonstrated that amides can be used in nickel‐catalyzed reactions that lead to cleavage of the amide C−N bond, with formation of a C−C or C−heteroatom bond. However, the general scope of these methodologies has been restricted to amides where the carbonyl is directly attached to an arene or heteroarene. We now report the nickel‐catalyzed esterification of amides derived from aliphatic carboxylic acids
Crucial for this transformation is the addition of sodium iodide, which provides in situ more active alkyl iodides. In the presence of a Rh(I)-DPPP catalyst system diverse esters (81 examples) including industrially relevant acetates from chloro- and dichloromethane can be prepared in a straightforward manner in up to 95% isolated yield. The used ligand not only affects the selectivity of the carbonylation