Thiourea dioxide promoted efficient organocatalytic one-pot synthesis of a library of novel heterocyclic compounds
作者:Sanny Verma、Subodh Kumar、Suman L. Jain、Bir Sain
DOI:10.1039/c1ob05818e
日期:——
The utility of thiourea dioxide as an efficient organocatalyst for the library synthesis of novel heterocyclic compoundsvia one-pot multicomponent coupling reactions is disclosed. Thiourea dioxide is an inexpensive and readily accessible catalyst, resulting in better product yields as compared to the corresponding thiourea as catalyst. Thiourea dioxide is found to be insoluble in various organic solvents and therefore at the end of the reaction products can be separated by extraction with diethyl ether and the recovered catalyst can be used several times with consistent catalytic activity.
Oxidative C-H/C-H Coupling of Dipyrromethanes with Azines by TiO2-Based Photocatalytic System. Synthesis of New BODIPY Dyes and Their Photophysical and Electrochemical Properties
作者:Maria A. Trestsova、Irina A. Utepova、Oleg N. Chupakhin、Maksim V. Semenov、Dmitry N. Pevtsov、Lyubov M. Nikolenko、Sergey A. Tovstun、Anna V. Gadomska、Alexander V. Shchepochkin、Gregory A. Kim、Vladimir F. Razumov、Irina B. Dorosheva、Andrey A. Rempel
DOI:10.3390/molecules26185549
日期:——
Oxidative C-H/C-H coupling reactions of dipyrromethanes with azines in the presence of a heterophase oxidative photocatalytic system (O2/TiO2/visible light irradiation) were carried out. As a result of cyclization of obtained compounds with boron trifluoride etherate, new hetaryl-containing derivatives of 4,4-difluoro-4-boron-3a,4a-diaza-s-indacene were synthesized. For the obtained compounds, absorption
A mild, efficient and metal-free method was described for the green synthesis of dipyrromethanes from aldehydes and unsubstituted pyrrole catalyzed by SO3H-functionalized ionicliquids (SO3H-ILs) in aqueousmedia at room temperature. Notably, SO3H-ILs, 1-butylsulfonic-3-methylimidazolium hydrogen sulfate ([bsmim][HSO4]) was the most efficient catalyst for moderate to good yields of the corresponding
Fast and Eco-friendly Synthesis of Dipyrromethanes by H<sub>2</sub>SO<sub>4</sub>·SiO<sub>2</sub>Catalysis under Solvent-free Conditions
作者:Yan Zhang、Jun Liang、Zhicai Shang
DOI:10.1002/cjoc.201090063
日期:2010.2
For the first time, sillica‐supported sulfuric acid has been used as a heterogeneous, reusable and efficient catalyst at room temperature to give the corresponding dipyrromethanes in a very short reaction time. The new reaction procedure is simple and solvent is not required.
reveal that dibromination does not occur on the pyrrolic moiety. The intermolecular interactions involving C⋯H, F⋯H, H⋯H, and Br⋯H are the key factors in stabilizing the molecular crystal packing. The antibacterial properties of these dyes were investigated and the brominated derivatives showed better antibacterial effects than their corresponding parent BODIPYs, particularly the unusual dibromo derivative
合成并表征了一系列单溴和二溴BODIPY(1-5),以研究染料对抗菌活性的性能。在BODIPY核心的2位和2,6-位进行区域选择性溴化反应,定量收率。内消旋-(4-羟苯基)BODIPY(5)的溴化反应出乎意料的二溴衍生物,其中溴基团安装在苯环的3,5-位而不是BODIPY核的2,6-位,由紫外线可见,荧光和1证实并支持1 H NMR光谱分析,电化学研究以及还通过单晶X射线晶体学。对于在BODIPY核心处安装的每个溴基团,我们观察到CH 2 Cl 2的吸收光谱中的红移约为16nm,发射光谱中的偏移为20-29nm 。母体和二溴衍生物的一阶还原电位之间的微小差异(5和5b)表明在溴的部分上没有发生二溴化反应。涉及C⋯H,F⋯H,H⋯H和Br⋯H的分子间相互作用是稳定分子晶体堆积的关键因素。研究了这些染料的抗菌特性,溴化衍生物显示出比其相应的母体BODIPY更好的抗菌效果,尤其是不寻常的二溴衍生物5b。