Silver-catalyzed one-step synthesis of multiply substituted quinolines
摘要:
A silver-catalyzed formation of C-C bond for the construction of a series of polysubstituted quinolines from arylamines, aldehydes, and ketones or arylamines and 1,3-diketones has been developed. The transformation is effective for a broad range of substrates, thus enabling the expansion of constituent architectures on the heterocyclic framework. This use of a single catalytic system to mediate chemical transformations in a synthetic operation is important for the development of new atom-economic strategies and this strategy is efficient in building complex structures from simple starting materials in an environmentally benign fashion. (C) 2015 Elsevier Ltd. All rights reserved.
A facile and effective synthesis of 2-azetidinones via phosphonitrilic chloride
作者:Maaroof Zarei
DOI:10.1016/j.tet.2013.05.121
日期:2013.8
The Staudinger reaction of imines to β-lactams was successfully achieved with substituted acetic acid and phosphonitrilicchloride in one-pot under mild conditions. Several types of β-lactams, especially 3-electron-withdrawing group β-lactams, can be synthesized by this versatile and efficient method in good to excellent yields. This method is simple, clean, and the by-products were removed by simple
Hydrogen-Bonding Asymmetric Metal Catalysis with α-Amino Acids: A Simple and Tunable Approach to High Enantioinduction
作者:Yingdong Lu、Tim C. Johnstone、Bruce A. Arndtsen
DOI:10.1021/ja904185b
日期:2009.8.19
While asymmetric transition-metal catalysis has become a powerful method for constructing chiral products, a challenge in this field is the identification of the correct ligand for high selectivity. We report here a simple approach to chiral catalyst formation: coupling of an available pool of Brønsted acids, namely, amino acid derivatives, with tunable ligands on copper catalysts. This system can
Substituent Cross-Interaction Effects on the Electronic Character of the CN Bridging Group in Substituted Benzylidene Anilines − Models for Molecular Cores of Mesogenic Compounds. A <sup>13</sup>C NMR Study and Comparison with Theoretical Results
作者:Helmi Neuvonen、Kari Neuvonen、Ferenc Fülöp
DOI:10.1021/jo0600508
日期:2006.4.1
could be verified. The electroniceffects of the neighboring aromatic ring substituents systematically modify the sensitivity of the CN group to the electroniceffects of the benzylidene or aniline ring substituents. Electron-withdrawing substituents on the aniline ring decrease the sensitivity of δC(CN) to the substitution on the benzylidine ring, while electron-donating substituents have the opposite
在CDCl 3中,对一系列介晶分子模型化合物(即C 13)测量了13 C NMR化学位移δC (C N)。取代的亚苄基苯胺p -X C 6 H 4 CH NC 6 H 4 p -Y(X = NO 2,CN,CF 3,F,Cl,H,Me,MeO或NMe 2; Y = NO 2,CN ,F,Cl,H,Me,MeO或NMe 2)。δ的取代基依赖性Ç(CN)被用作研究电子取代基对偶氮甲碱单元的作用的工具。亚苄基取代基X有δ的反向效应Ç(C N):吸电子原因屏蔽的取代基,而给电子性的人的行为相反,感应效果清楚地在共振效应为主。相反,苯胺取代基Y发挥正常作用:吸电子取代基引起屏蔽,而供电子取代基引起C N碳屏蔽,感应效应和共振效应的强度非常相似。此外,可以验证X和Y之间是否存在特定的交叉相互作用。相邻芳环取代基的电子效应可系统地改变C的灵敏度N基团对亚苄基或苯胺环取代基的电子作用。吸电子苯胺环上的取代基降低δ的灵敏度Ç(C
Grinding Synthesis of Schiff Bases Combined with Infrared Irradiation
作者:Jian-Ying Tong、Na-Bo Sun、Hong-Ke Wu
DOI:10.14233/ajchem.2013.14382
日期:——
Solid-phase synthesis combined with infrared irradiation promoted the formation of a series of Schiff bases in the condensation reaction between substituted benzaldehydes and anilines, in the solvent free. Benzaldehydes and anilines, containing either electron withdrawing or electron-releasing groups, were evaluated their substituent effect on the formation of the Schiff bases. Moreover, this new procedure is environmentally benign because no solvent was employed in the transformations.
Triarylmethyl Cation‐Catalyzed Three‐Component Coupling for the Synthesis of Unsymmetrical Bisindolylmethanes
作者:William J. Patterson、Kelly Lucas、Vanessa A. Jones、Zhenghua Chen、Kevin Bardelski、Melissa Guarino‐Hotz、Cheyenne S. Brindle
DOI:10.1002/ejoc.202100946
日期:2021.12.28
cations catalyze the synthesis of unsymmetrical bisindolylmethanes fromimines and two different indoles. Optimization of the catalyst by tuning cation stability allows for excellent single addition selectivity. The single additionintermediates can be isolated or used in situ in a high-yielding one-pot two-step reaction to generate unsymmetrical bisindolylmethanes.