Zirconium catalyzed amide formation without water scavenging
作者:Helena Lundberg、Fredrik Tinnis、Hans Adolfsson
DOI:10.1002/aoc.5062
日期:2019.9
A scalable homogeneous metal‐catalyzed protocol for direct amidation of carboxylic acids is presented. The use of 2–10 mol% of the commercially available Zr(Cp)2(OTf)2·THF results in high yields of amides at moderate temperature, using an operationally convenientreaction protocol that circumvents the use of water scavenging techniques.
Catalytic Chemical Amide Synthesis at Room Temperature: One More Step Toward Peptide Synthesis
作者:Tharwat Mohy El Dine、William Erb、Yohann Berhault、Jacques Rouden、Jérôme Blanchet
DOI:10.1021/acs.joc.5b00378
日期:2015.5.1
An efficient method has been developed for direct amide bond synthesis between carboxylic acids and amines via (2-(thiophen-2-ylmethyl)phenyl)boronic acid as a highly active bench-stable catalyst. This catalyst was found to be very effective at room temperature for a large range of substrates with slightly higher temperatures required for challenging ones. This methodology can be applied to aliphatic
N-(p-toluenesulfonyl)imidazole in the presence of triethylamine in DMF at 100 °C afforded the corresponding amides in good to excellent yields. N-(p-Toluenesulfonyl)imidazole proved to be a highly efficient coupling reagent for the preparation of numerous structurally diverse primary, secondary and tertiary amides.
在三乙胺的存在下,在 DMF 中,在 100 °C 下用 N-(对甲苯磺酰基)咪唑处理羧酸铵,得到相应的酰胺,收率良好至极好。N-(对甲苯磺酰基)咪唑被证明是一种高效的偶联剂,可用于制备多种结构不同的伯、仲和叔酰胺。
Ruthenium-catalysed oxidation of alcohols to amides using a hydrogen acceptor
作者:Andrew J.A. Watson、Russell J. Wakeham、Aoife C. Maxwell、Jonathan M.J. Williams
DOI:10.1016/j.tet.2014.04.017
日期:2014.6
A wider investigation into the synthesis of secondary amides from primary alcohols using a hydrogen acceptor using commercially available [Ru(p-cymene)Cl-2](2) with bis(diphenylphosphino)butane (dppb) as the catalyst. The report looks at over 50 examples with varying functionality and steric bulk, whilst also covering the first reported results using microwave heating to effect the transformation. (C) 2014 Elsevier Ltd. All rights reserved.