Irradiation of nitrogen-saturated acetonitrile solutions containing ethyl 3-amino-3-phenyl-2-propenoate derivatives with the (Z)-configuration [(Z)-1] and 10-methylacridinium perchlorate (MAP) at wavelengths longer than 340 nm afforded the corresponding pyrrole derivatives in good to high yields without exhibiting a profound effect related to the substituents. An analysis of the Stern-Volmer plots for the fluorescence quenching of MAP by (Z)-1 showed that this sensitizer fluorescence is efficiently quenched, and hence electron transfer is confirmed to be involved in the primary process of the MAP-sensitized cyclization reactions of 1.
Electrochemical Oxidative Cyclization: Synthesis of Polysubstituted Pyrrole from Enamines
作者:Zhiwei Chen、Guang Shi、Wei Tang、Jie Sun、Wenxing Wang
DOI:10.1002/ejoc.202001484
日期:2021.2.12
Diverse polysubstituted pyrroles were synthesized through electrochemical oxidative cyclization of enamines under mild conditions. By avoiding the use of metal catalysts and oxidants, this method is both more environmentally friendly and atomic economic than other synthetic protocols.
Task-Specific Basic Ionic Liquid: A Reusable and Green Catalyst for One-Pot Synthesis of Highly Functionalized Pyrroles in Aqueous Media
作者:Issa Yavari、Elaheh Kowsari
DOI:10.1055/s-2008-1042912
日期:2008.4
A basic functionalizedionicliquid, 1-butyl-3-methylimidazolium hydroxide ([bmim]OH), catalyzed the three-component condensation reaction of acid chlorides, amino acids, and dialkyl acetylenedicarboxylates in water to afford functionalized pyrroles in high yields.
A photocatalytic formal [3+2] cycloaddition of 2H‐azirines with alkynes has been achieved under irradiation by visiblelight in the presence of organic dye photocatalysts. This transformation provides efficient access to highly functionalized pyrroles in good yields and has been applied to the synthesis of drug analogues. A primary trial of photocascade catalysis merging energy transfer and redox neutral
在有机染料光催化剂的存在下,在可见光照射下,已实现了2 H H叠氮基与炔烃的光催化形式[3 + 2]环加成反应。这种转化提供了以高收率高效获得高度官能化吡咯的途径,并已应用于药物类似物的合成。光级联催化合并能量转移和氧化还原中性反应的初步试验显示是成功的。
Trifluoroethanol as a Unique Additive for the Chemoselective Electrooxidation of Enamines to Access Unsymmetrically Substituted NH‐Pyrroles
作者:Mrinmay Baidya、Debabrata Maiti、Lisa Roy、Suman De Sarkar
DOI:10.1002/anie.202111679
日期:2022.1.26
A chemoselective electrooxidative heterocoupling of two different enamines is reported for the synthesis of unsymmetricallysubstituted NH-pyrroles. A “magic effect” of the additive trifluoroethanol is utilized to achieve the desired chemoselectivity by tuning the oxidation potentials and controlling the activation energy of the rate-determining step.
Synthesis of highly substituted pyrroles via oxidative free radical reactions of β-aminocinnamates
作者:An-I Tsai、Che-Ping Chuang
DOI:10.1016/j.tet.2005.12.011
日期:2006.3
reactions of β-aminocinnamates are described. Imine radicals produced by tetra-n-butylammonium cerium(IV) nitrate (TBACN) oxidation of enamines undergo efficient addition to the C–C double bond of β-aminocinnamates. This TBACN mediated free radical reaction between β-aminocinnamates and enamines provides a novel method for the synthesis of highly substitutedpyrroles. The direct TBACN oxidation of β-aminocinnamates