作者:Manuel van Gemmeren、Carlos Santiago、Hao Chen、Arup Mondal
DOI:10.1055/s-0040-1706014
日期:2022.3
for the late-stage olefination of arenes. Building upon a method previously developed for simple arenes, a variety of complexarene substrates were functionalized. Importantly, the method uses the arene as a limiting reactant and is therefore suitable for valuable starting materials that cannot be used in excess. The regioselectivity of the transformation is controlled by the steric and electronic properties
Green Esterification of Carboxylic Acids Promoted by
<i>tert</i>
‐Butyl Nitrite
作者:Yonggao Zheng、Yanwei Zhao、Suyan Tao、Xingxing Li、Xionglve Cheng、Gangzhong Jiang、Xiaobing Wan
DOI:10.1002/ejoc.202100326
日期:2021.5.14
TBN‐catalyzed green esterification of carboxylicacids has been developed, which features a broad range of substrates and excellent functional groups tolerance. The mechanistic study confirmed that the nitrous acid formed in situ in the system is the actual catalyst for this transformation.
Palladium-Catalyzed Late-Stage Direct Arene Cyanation
作者:Da Zhao、Peng Xu、Tobias Ritter
DOI:10.1016/j.chempr.2018.09.027
日期:2019.1
Methods for direct benzonitrile synthesis are sparse, despite the versatility of cyano groups in organic synthesis and the importance of benzonitriles for the dye, agrochemical, and pharmaceutical industries. We report the first general late-stage aryl C–H cyanation with broad substrate scope and functional-group tolerance. The reaction is enabled by a dual-ligand combination of quinoxaline and an
Sterically Controlled Late-Stage C–H Alkynylation of Arenes
作者:Arup Mondal、Hao Chen、Lea Flämig、Philipp Wedi、Manuel van Gemmeren
DOI:10.1021/jacs.9b10868
日期:2019.11.27
Phenylacetylenes are key structural motifs in organic chemistry, which find widespread applications in bioactive molecules, synthetic intermediates, functional materials and reagents. These molecules are typically prepared from pre-functionalized starting materials, e.g. using the Sonogashiracoupling, or using directing group-based C-H activation strategies. While highly efficient, these approaches
[EN] PROCESS FOR THE PREPARATION OF NATEGLINIDE<br/>[FR] PROCEDE DE FABRICATION DE NATEGLINIDE
申请人:CIPLA LTD
公开号:WO2005121071A1
公开(公告)日:2005-12-22
One-pot process for the preparation of nateglinide, which process comprises reacting an alkyl ester of D-phenylalanine of formula (II) where R represents C1-4 alkyl, typically methyl, either as the free base or in salt form (typically the hydrochloride), with trans-4-isopropylcyclohexanecarboxylic acid of formula (III) where X represents hydroxy or halo, typically chloro, to obtain a C1-4 alkyl ester of nateglinide of formula (IV), preferably the methyl ester of nateglinide followed by hydrolysis to yield nateglinide of formula (I).