制备了25种以上的咪唑鎓盐(根据其空间和电子特性的不同而选择),并使用包围指示剂方法确定了其p K a值。通过咪唑阳离子结构的系统变化,确定了杂环上每个位置的取代基的变化。特别是,使用Hammett参数对电子效果的传输进行了量化。这些新数据表明了去质子化所需的碱基强度以及将这些数据与相应碳烯的亲核性相关联的潜力。
Efficient Synthesis of γ-Keto Sulfones by NHC-Catalyzed Intermolecular Stetter Reaction
摘要:
The N-heterocyclic carbene-catalyzed intermolecular Stetter reaction of aldehydes with alpha,beta-unsaturated sulfones allows the atom-economic and selective formation of gamma-keto sulfones in good yields. Key to the success of this unique transition-metal-free carbon-carbon bond-forming reaction is the right choice of the NHC precursor and base. The reaction tolerates a broad range of different aldehydes.
Revelation from the Reaction of 1,4-Diazabutadiene with Perchloric Acid: An Approach to the Synthesis of Imidazolium Perchlorates
作者:Hongxing Xin、Xiaohe Zhu、Hong Yan、Xiuqing Song
DOI:10.1002/jhet.1847
日期:2016.9
The reactions of 1,4‐diazabutadienes 1 with HClO4 were studied in detail. The final products obtained were not the hydroperchlorates of 1 but imidazolium perchlorates 2 or 3. A possible reaction process is postulated on the basis of the isolation of the intermediate 2‐iminomethylimidazolium salt 4. The factors influencing the conversion of 4 to the imidazolium perchlorates 2 and 3 were discussed with
Synthesis, Antitumor Activity, and Docking Study of 1,3-Disubstituted Imidazolium Derivatives
作者:Q. W. Fan、Q. D. Zhong、H. Yan
DOI:10.1134/s1070363217120489
日期:2017.12
A series of 1,3-disubstituted imidazolium salts were synthesized through a convenient synthetic approach based on the reaction of 1,4-diazabuta-1,3-dienes with HClO4. Their antitumor activity was evaluated in vitro against a number of human cancer cells. 1,3-Bis[(3,5-bis(trifluoromethyl)phenyl]imidazolium perchlorate turned out to be the most active against A549 and MCF-7 cancer cell lines with IC50 values of 5.24 and 4.21 mu M, respectively. The results of structure-activity relationship study indicated that substituents on the imidazole derivatives play an important role in their cytotoxic activities. Finally, molecular docking of some tested compounds was carried out in order to investigate their binding pattern with the CDK2.