制备了一系列的单取代的嘧啶鎓和吡嗪鎓三氟甲磺酸酯和3,5-二取代的吡啶鎓三氟甲磺酸酯,并使用硫氧化作为模型反应,对过氧化氢的简单氧化催化剂进行了测试。它们的催化效率在很大程度上取决于取代基的类型,并且对于具有吸电子基团的衍生物而言是显着的,其反应性与黄酮盐相当,后者是氧合作用的主要有机催化剂。由于它们的高稳定性和良好的可及性,4-(三氟甲基)嘧啶鎓和3,5-二硝基吡啶鎓三氟甲磺酸盐是选择的催化剂,并显示出催化脂肪族和芳香族硫化物氧化为亚砜的作用,定量转化率高,制备产率高,并且具有优异的性能。化学选择性。K R +值(p K R + <5)和较小的负还原电位(E red > -0.5 V)。在催化氧化过程中原位形成的过氧化氢加合物充当底物氧化剂。通过在B3LYP / 6-311 ++ g(d,p)水平上的计算获得的从这些杂环氢过氧化物到硫代苯甲醚的转移的吉布斯自由能表明,它们是比烷基氢过氧化
CH Activation by Amide Chelation Control: Ruthenium‐ Catalyzed Direct Synthesis of 2‐Aryl‐3‐furanamides
作者:Yigang Zhao、Victor Snieckus
DOI:10.1002/adsc.201400147
日期:2014.5.5
methodology for the synthesis of heterobiaryls by the ruthenium‐catalyzedCH activation/cross‐coupling of heterocyclic amides with aryl boroneopentylates is surveyed. From this survey, the highly regioselective reaction of furan‐3‐carboxamide to give 2‐aryl‐3‐furanamides is optimized and generalized in scope with respect to the aryl boroneopentylate coupling partners. Established thereby is a one‐step synthetic
Silver acetate-assisted formation of amides from acyl chlorides
作者:A. Leggio、E.L. Belsito、M.L. Di Gioia、V. Leotta、E. Romio、C. Siciliano、A. Liguori
DOI:10.1016/j.tetlet.2014.11.067
日期:2015.1
acid chlorides to give amides is disclosed. Reactions are carried out in the presence of silver acetate in non-aqueous environments under heterogeneous phase conditions. Amides are easily recovered in very good to excellent yields and without racemization. The approach is successful in forming peptide bonds starting from N-(4-nitrobenzenesulfonyl)-amino acid chlorides and allows the formation of dipeptides
Studies on Pyrazines; 21.<sup>1</sup>A Convenient Synthesis of Pyrazinecarboxylic Acid Derivatives from Chloropyrazines
作者:Ryo Takeuchi、Katsunobu Suzuki、Nobuhiro Sato
DOI:10.1055/s-1990-27055
日期:——
Palladium-catalyzed carbonylation of chloropyrazines in methanol led to pyrazinecarboxylic esters in good yields. Similarly, pyrazinecarboxamides were obtained by using dialkylamines or alkylamines as the solvent.
One-pot synthesis of amides from carboxylic acids activated using thionyl chloride
作者:A. Leggio、E. L. Belsito、G. De Luca、M. L. Di Gioia、V. Leotta、E. Romio、C. Siciliano、A. Liguori
DOI:10.1039/c5ra24527c
日期:——
A one-pot synthesis of secondary and tertiary amides from carboxylic acids and amines by using SOCl2 has been developed. Also when sterically hindered amines were used as the starting materials, excellent yields of the corresponding amides were obtained. The amidation of N-protected α-amino acids with secondary amines proceeds effectively with good yields. The process works well also in the presence
A CB2 receptor modulator comprising an imidazole derivative represented by the general formula (I):
[wherein, R
1
represents optionally substituted lower alkyl or the like; R
2
represents optionally substituted cycloalkyl or the like; R
3
represents optionally substituted aryl or the like; and n represents an integer of 0 to 3] or a pharmaceutically acceptable salt thereof as an active ingredient, and the like are provided.