14191-09-4Relevant articles and documents
Iron-Catalyzed Synthesis of Substituted Thiazoles from Enamines and Elemental Sulfur through C?S Bond Formation
Wu, Mingzhong,Jiang, Yong,An, Zhenyu,Qi, Zhenjie,Yan, Rulong
, p. 4236 - 4240 (2018)
An atom economical approach for the synthesis of substituted thiazoles starting from enamines and elemental sulfur through the C?H functionalization/C?S bond formation is described. Under the optimized conditions, various substituted enamines reacted smoothly with elemental sulfur and the desired substituted thiazoles were generated in moderate to excellent yields. (Figure presented.).
Electrochemical Oxidative Cyclization: Synthesis of Polysubstituted Pyrrole from Enamines
Chen, Zhiwei,Shi, Guang,Tang, Wei,Sun, Jie,Wang, Wenxing
supporting information, p. 951 - 955 (2021/02/03)
A conceptually novel method for the preparation of pyrrole is described by electrochemical-oxidation-induced intermolecular annulation via enamines. In a simple undivided cell, based on a sodium acetate-facilitated, polysubstituted pyrrole derivations has been facilely synthesized under external oxidant-free condition. This electrosynthetic approach providing an environmentally benign protocol for C?C bond cross-coupling and oxidative annulation, which features unparalleled broad scope of substrates and practicality.
Photocatalytic Visible-Light-Induced Nitrogen Insertion via Dual C(sp3)-H and C(sp2)-H Bond Functionalization: Access to Privileged Imidazole-based Scaffolds
Patel, Srilaxmi M.,P., Ermiya Prasad,Bakthadoss, Manickam,Sharada, Duddu S.
supporting information, p. 257 - 261 (2021/01/15)
Here we have demonstrated a visible-light-mediated metal-free organic-dye-catalyzed dehydrogenative N-insertion leading to highly substituted imidazoles and privileged dihydroisoquinoline-based imidazole derivatives via C(sp3)-H and C(sp2)-H bond functionalization. A sustainable, convenient, metal-free azidation/C-H aminative cyclization approach in the absence of stoichiometric oxidants is presented. This protocol involves a rare photoinduced iminyl radical as a key intermediate for the "N"insertion.
5-Hydroxyindole-based EZH2 inhibitors assembled via TCCA-catalyzed condensation and Nenitzescu reactions
Chen, Guoliang,Du, Fangyu,Sun, Wenjiao,Wang, Lihui,Wu, Chunfu,Yang, Cheng,Zhou, Qifan
, (2020/05/16)
5-Hydroxyindole derivatives have various demonstrated biological activities. Herein, we used 5-hydroxyindole as a synthetic starting point for structural alterations in a combinatorial process to synthesize 22 different compounds with EZH2 inhibitor pharmacophores. A series of 5-hydroxyindole-derived compounds were screened inhibitory activities against K562 cells. According to molecular modeling and in vitro biological activity assays, the preliminary structure-activity relationship was summarized. Compound L–04 improved both the H3K27Me3 reduction and antiproliferation parameters (IC50 = 52.6 μM). These findings revealed that compound L–04 is worthy of consideration as a lead compound to design more potent EZH2 inhibitors. During the preparation of compounds, we discovered that trichloroisocyanuric acid (TCCA) is a novel catalyst which demonstrates condensation-promoting effects. To gain insight into the reaction, in situ React IR technology was used to confirm the reactivity. Different amines were condensed in high yields with β-diketones or β-ketoesters in the presence of TCCA to afford the corresponding products in a short time (10~20 min), which displayed some advantages and provided an alternative condensation strategy.
Catalytic Mechanism Study on the 1,2- and 1,4-Transfer Hydrogenation of Ketimines and β-Enamino Esters Catalyzed by Axially Chiral Biscarboline-Based Alcohols
Dong, Mengxian,Wang, Jie,Wu, Shijie,Zhao, Yang,Ma, Yangyang,Xing, Yongfei,Cao, Fei,Li, Longfei,Li, Zhenqiu,Zhu, Huajie
supporting information, p. 4602 - 4610 (2019/08/30)
Axial N-O alcohols, which have two large carboline moieties connected to the axis were synthesized and used in catalytic enantioselective 1,2- and 1,4-transfer hydrogenations of total 26 ketimines and β-enamino esters. Excellent levels of enantioselectivity ranging from 91% to 99% were achieved by using catalyst (aS)-(S)-3,3′-bis((S)-2-(hydroxymethyl)pyrrolidine-1-carbonyl)-9,9′-dimethyl-9H,9′H-[1,1′-bipyrido[3,4-b]indole] 2-oxide. Interestingly, a mixture of (aS)-(S)-3,3′-bis((S)-2-(hydroxymethyl)pyrrolidine-1-carbonyl)-9,9′-dimethyl-9H,9′H-[1,1′-bipyrido[3,4-b]indole] 2-oxide and (aR)-(S)-3,3′-bis((S)-2-(hydroxymethyl)pyrrolidine-1-carbonyl)-9,9′-dimethyl-9H,9′H-[1,1′-bipyrido[3,4-b]indole] 2-oxide was also able to provide high enantioselectivities up to 95% that is the same as that using pure (aS)-(S)-3,3′-bis((S)-2-(hydroxymethyl)pyrrolidine-1-carbonyl)-9,9′-dimethyl-9H,9′H-[1,1′-bipyrido[3,4-b]indole] 2-oxide. A plausible catalytic mechanism was suggested and total four kinds of transition states (TS) including almost 60 TS structures were investigated using density functional theory (DFT) with different basis sets such as 6-311G(2d,p). The predicted activation energy data are consistent with the experimental results. (Figure presented.).
Visible Light Initiated Hantzsch Synthesis of 2,5-Diaryl-Substituted Pyrroles at Ambient Conditions
Lei, Tao,Liu, Wen-Qiang,Li, Jian,Huang, Mao-Yong,Yang, Bing,Meng, Qing-Yuan,Chen, Bin,Tung, Chen-Ho,Wu, Li-Zhu
supporting information, p. 2479 - 2482 (2016/06/09)
Irradiation of a mixture of enamines and α-bromo ketones, with a catalytic amount of Ir(ppy)3 by visible light (Λ= 450 nm), enables the production of various 2,5-diaryl-substituted pyrroles in good to excellent yields. The key intermediates in
Tandem Copper-Catalyzed Propargylation/Alkyne Azacyclization/Isomerization Reaction under Microwave Irradiation: Synthesis of Fully Substituted Pyrroles
Zhang, Xiao-Yan,Yang, Zhi-Wei,Chen, Zhongzhu,Wang, Jun,Yang, Dong-Lin,Shen, Ze,Hu, Li-Li,Xie, Jian-Wu,Zhang, Jin,Cui, Hai-Lei
, p. 1778 - 1785 (2016/03/15)
A copper-catalyzed and microwave-assisted synthesis of fully substituted pyrroles has been developed. A series of pentasubstituted pyrroles, especially α-arylpyrroles, could be obtained in moderate to good yields (up to 93%) through a tandem propargylation/alkyne azacyclization/isomerization sequence from readily available β-enamino compounds and propargyl acetates.
A chemoselective route to β-enamino esters and thioesters
Xin, Dongyue,Burgess, Kevin
supporting information, p. 2108 - 2110 (2014/05/06)
Conditions were developed for syntheses of β-enamino esters, thioesters, and amides. These reactions involve hydroxybenzotriazole derivatives in buffered media. Illustrative syntheses of some heterocyclic systems are given, including some related to protein-protein interface mimics.
Synthesis of chiral β-amino acid derivatives by asymmetric hydrosilylation with an imidazole derived organocatalyst
Jones, Simon,Li, Xianfu
experimental part, p. 5522 - 5532 (2012/09/21)
The organocatalysed asymmetric hydrosilylation of a number of N-aryl and alkyl β-substituted enamino esters proceeds in generally good yield and enantioselectivity. Crucial to obtaining high yield and selectivity was the addition of benzoic acid as an additive and under these conditions, both N-alkyl and N-aryl substituents were well tolerated. β-Aryl and alkyl substituents were evaluated and a model proposed to account for the experimental observations based upon enamine tautomerisation and conformational preferences of the reactive ketimine intermediate.
Chiral lewis base catalyzed highly enantioselective reduction of N-alkyl β-enamino esters with trichlorosilane and water
Wu, Xinjun,Li, Yang,Wang, Chao,Zhou, Li,Lu, Xiaoxia,Sun, Jian
supporting information; experimental part, p. 2846 - 2848 (2011/04/24)
First, test the water! In the presence of a chiral Lewis base catalyst 2, the supposedly moisture-unfriendly reduction system with trichlorosilane was found to be highly efficient and enantioselective when using water as an additive. For the first time, this method enables the reduction of a broad range of N-alkyl β-enamino esters 1 to give N-alkyl β-amino esters 3 in good to high yields and with excellent enantioselectivities (see scheme).
