A simple ketone as an efficient metal-free catalyst for visible-light-mediated Diels–Alder and aza-Diels–Alder reactions
作者:Jiri Kollmann、Yu Zhang、Waldemar Schilling、Tong Zhang、Daniel Riemer、Shoubhik Das
DOI:10.1039/c9gc00485h
日期:——
Diels–Alder reactions are highly effective between electron-rich dienes and electron-poor dienophiles. However, these reactions with electron-rich dienophiles are limited and require forcing conditions. Based on this, an efficientmetal-free homogeneous system has been developed for the Diels–Alder reactions between electron-rich dienophiles and dienes under visible-light conditions. Additionally,
Oxidation and Deprotection of Primary Benzylamines by Visible Light Flavin Photocatalysis
作者:Burkhard König、Robert Lechner
DOI:10.1055/s-0029-1218709
日期:2010.5
We report a photocatalytic oxidation procedure that can be used to convert benzylamines into their corresponding aldehydes under mild conditions without over-oxidation, using riboflavin tetraacetate as photocatalyst and blue emitting LEDs (440 nm) as light source. Oxygen is the terminal oxidant and H2O2 and NH3 appear as the only byproducts of the oxidation of primary benzylamines. Furthermore, we have developed a photocatalytic protocol for 4-methoxybenzyl (Mob) group deprotection of primary amines and alcohols. Double bonds, benzyl-protected esters and alcohols are tolerated under the applied conditions, whereas the deprotection of protected secondary amines is not applicable. Mob-protected carboxylic acids and carboxybenzoyl (Cbz) protected amines are inert under the photodeprotection conditions.
One Pot Photoredox Decarboxylation Reaction of<i>N</i>-Cyano(α-bromo-α-phenyl)methylanilines Leading to Synthesis of Four-Membered Cyclic Carbamates
作者:Manpreet Kaur、Baldev Singh
DOI:10.1002/jhet.1776
日期:2014.5
A new four‐membered cycliccarbamates have been synthesized through solar irradiation of N‐cyano(α‐bromo‐α‐phenyl)methylanilines in their aqueous methanolic solution using iodide salt in basic medium. These compounds have been characterized as 3,4‐diphenyl‐1,3oxazetidin‐2‐one through their elemental analysis, IR, 1H‐NMR, 13C‐NMR, and mass spectral studies.
2,3-Dihydro-1,2-Diphenyl-substituted 4H-Pyridinone Derivatives as New Anti Flaviviridae Inhibitors
作者:Antonella Peduto、Antonio Massa、Antonia Di Mola、Paolo de Caprariis、Paolo La Colla、Roberta Loddo、Sergio Altamura、Giovanni Maga、Rosanna Filosa
DOI:10.1111/j.1747-0285.2011.01102.x
日期:2011.6
With the aim of identifying novel lead compounds active against emergent human infectious diseases, a series of 2,3‐dihydro‐4H‐pyridinone derivatives has been prepared and evaluated for antiviral activity. Compounds were evaluated in vitro in cell‐based assays for cytotoxicity and against a wide spectrum of viruses. In the antiviral screening, several compounds showed to be fairly active against viruses
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