amidation of unactivated esters with amines under transition-metal-free and solvent-freeconditions, affording a series of amides in good to excellent yields at room temperature. In particular, an environmentally friendly and practical workup procedure, which circumvents the use of organic solvents and chromatography in most cases, was disclosed. Moreover, the gram-scale production of representative products
在本文中,开发了一种NaO t Bu介导的合成方法,用于在无过渡金属和无溶剂的条件下将未活化的酯与胺直接酰胺化,从而在室温下以良好或优异的收率提供了一系列酰胺。特别地,公开了一种环境友好且实用的后处理程序,其在大多数情况下避免了有机溶剂和色谱的使用。此外,代表产品3a,3w和3au的克级生产通过应用操作简单,可持续和实用的程序有效地实现了这一目标。此外,该方法也适用于有价值的分子的合成,例如莫氯贝胺(一种强效抗抑郁药),苯达尼尔和芬呋喃(两种市售农业杀菌剂)。这些结果表明该方案具有简化工业中酰胺合成的潜力。同时,对所有目标产品的定量绿色指标进行了评估,这表明本协议在环境友好性和可持续性方面优于已报道的协议。最后,还进行了额外的实验和计算计算,以阐明这种转换的机理见解,
Copper(<scp>i</scp>)-catalyzed amidation reaction of organoboronic esters and isocyanates
作者:Tedrick Thomas Salim Lew、Diane Shu Wen Lim、Yugen Zhang
DOI:10.1039/c5gc01374g
日期:——
A simple and efficient methodology for the preparation of amides from easily available organoboronic esters and isocyanates has been accomplished using ligand-free copper(I) catalyst. The reaction system demonstrated broad substrate...
Direct Amidation of <i>N</i>-Boc- and <i>N</i>-Cbz-Protected Amines via Rhodium-Catalyzed Coupling of Arylboroxines and Carbamates
作者:Diane S. W. Lim、Tedrick T. S. Lew、Yugen Zhang
DOI:10.1021/acs.orglett.5b03061
日期:2015.12.18
N-Boc- and N-Cbz-protected amines are directly converted into amides by a novel rhodium-catalyzed coupling of arylboroxines and carbamates, replacing the traditional two-step deprotection-condensation sequence. Both protected anilines and aliphatic amines are efficiently transformed into a wide variety of secondary benzamides, including sterically hindered and electron-deficient amides, as well as in the presence of acid-labile and reducible functional groups.