selective aromatic deuteriation of various sulfonylureas and tertiary sulfonamides, as well as for a broad range of secondary sulfonamides. Based on a comprehensive screening of readily available Ir catalysts, the Kerr-type NHC catalyst 5 proved to be most efficient in the HIE reaction of secondary sulfonamides and sulfonylureas. However, for tertiary sulfonamides, the commercially available Burgess catalyst
我们首次报告了各种磺酰脲类和叔磺酰胺以及各种仲磺酰胺的选择性芳烃氘化的优化氢同位素交换 (HIE) 条件。基于对容易获得的 Ir 催化剂的全面筛选,证明 Kerr 型 NHC 催化剂 5 在仲磺酰胺和磺脲类的 HIE 反应中最有效。然而,对于叔磺酰胺,尚未用于 HIE 反应的市售 Burgess 催化剂 6 导致氘的掺入量高得多。最后,我们测试了用于标记一系列磺胺药物的新 HIE 协议,并调整了条件以允许选择性氚标记。
Photochemistry of some group V onium salts. Effect of magnetic nuclei on in-cage radical coupling reactions
作者:David T. Breslin、Franklin D. Saeva
DOI:10.1021/jo00239a001
日期:1988.2
Evaluation of a P,N-ligated iridium(I) catalyst in hydrogen isotope exchange reactions of aryl and heteroaryl compounds
We have developed a novel and efficient iridium-catalyzed hydrogen isotopeexchangereaction method with secondary and tertiary sulfonamides at ambient temperatures. Furthermore N-oxides and phosphonamides have been successfully applied in hydrogen isotopeexchangereactions with moderate to excellent deuterium introduction.
Novel Water-Soluble β-Cyclodextrin−Calix[4]arene Couples as Fluorescent Sensor Molecules for the Detection of Neutral Analytes
作者:Jürgen Bügler、Johan F. J. Engbersen、David N. Reinhoudt
DOI:10.1021/jo9723321
日期:1998.8.1
The synthesis and the host-guest chemistry of two novel fluorescent beta-cyclodextrin-calix[4]arene couples 1 and 2 is described. The compounds were prepared by coupling a beta-cyclodextrin linked with an aminoxylyl spacer with two different calix[4]arene building blocks each bearing a fluorophore. The fluorophores attached to 1 and 2 are the 2-naphthylamine and the dansyl moiety, respectively. The unsymmetric calix[4]arene functionalization was achieved by monoprotection of the 1,3-diformylcalix[4]arene. The host molecules 1 and 2 were used as fluorescent probes for several organic analytes in aqueous solution. 1 shows sensitivity for a series of neutral organic guest species, such as steroids, terpenes, and other natural products. In contrast, compound 2 does not show sensitivity for organic analytes in aqueous solution. The different behavior of the two fluorescent probes 1 and 2 is explained by the different strength of self-inclusion of each fluorphoric group into the beta-cyclodextrin cavity.