170489-16-4Relevant academic research and scientific papers
Cobalt-Catalyzed Enantioselective C–H Arylation of Indoles
Ackermann, Lutz,Jacob, Nicolas,Oliveira, Jo?o C. A.,Wencel-Delord, Joanna,Zaid, Yassir
supporting information, p. 798 - 806 (2022/02/03)
Atropoisomeric (hetero)biaryls are scaffolds with increasing importance in the pharmaceutical and agrochemical industries. Although it is the most obvious disconnection to construct such compounds, the direct enantioselective C–H arylation through the concomitant induction of the chiral information remains extremely challenging and uncommon. Herein, the unprecedented earth-abundant 3d-metal-catalyzed atroposelective direct arylation is reported, furnishing rare atropoisomeric C2-arylated indoles. Kinetic studies and DFT computation revealed an uncommon mechanism for this asymmetric transformation, with the oxidative addition being the rate- and enantio-determining step. Excellent stereoselectivities were reached (up to 96% ee), while using an unusual N-heterocyclic carbene ligand bearing an essential remote substituent. Attractive dispersion interactions along with positive C–H-π interactions exerted by the ligand were identified as key factors to guarantee the excellent enantioselection.
Recyclable and reusablen-Bu4NBF4/PEG-400/H2O system for electrochemical C-3 formylation of indoles with Me3N as a carbonyl source
Cheng, Didi,Li, Jingyi,Li, Yujin,Ling, Fei,Liu, Lei,Liu, Tao,Zhong, Weihui
supporting information, p. 4107 - 4113 (2021/06/17)
A safe, practical and eco-friendly electrochemical methodology for the synthesis of 3-formylated indoles has been developed by the utilization of Me3N as a novel formylating reagent. Stoichiometric oxidants, metal catalysts, and activating agents were avoided in this method, and an aqueous biphasic system ofn-Bu4NBF4/PEG-400/H2O was used as a recyclable and reusable reaction medium, which made this electrosynthesis approach more sustainable and environmentally friendly. This process expanded the substrate scope and functional group tolerance for bothN-EDG andN-EWG indoles. Furthermore, late-stage functionalization and total/formal synthesis of drugs and natural products were realized by means of this route.
Electrochemically Enabled C3-Formylation and -Acylation of Indoles with Aldehydes
Yang, Liquan,Liu, Zhaoran,Li, Yujun,Lei, Ning,Shen, Yanling,Zheng, Ke
supporting information, p. 7702 - 7707 (2019/10/19)
Reported herein is an effective strategy for oxidative cross-coupling of indoles with various aldehydes. The strategy is based on a two-step transformation via a well-known Mannich-type reaction and a C-N bond cleavage for carbonyl introduction. The key step - the C-N bond cleavage of the Mannich product - was enabled by electrochemistry. This strategy (with over 40 examples) ensures excellent functional-group tolerance as well as late-stage functionalization of pharmaceutical molecules.
Access to Polycyclic Sulfonyl Indolines via Fe(II)-Catalyzed or UV-Driven Formal [2 + 2 + 1] Cyclization Reactions of N-((1H-indol-3-yl)methyl)propiolamides with NaHSO3
Lu, Lin,Luo, Chenguang,Peng, Hui,Jiang, Huanfeng,Lei, Ming,Yin, Biaolin
, p. 2602 - 2605 (2019/04/30)
A variety of structurally novel polycyclic sulfonyl indolines have been synthesized via FeCl2-catalyzed or UV-driven intramolecular formal [2 + 2 + 1] dearomatizing cyclization reactions of N-(1H-indol-3-yl)methyl)propiolamides with NaHSO3 in an aqueous medium. The reactions involve the formation of one C-C bond and two C-S bonds in a single step.
Method for performing formylation reaction of indole compound by photocatalysis of carbazolyl-conjugated micro-porous polymers (CMPs)
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Paragraph 0035-0040, (2018/07/30)
The invention discloses a method for performing formylation reaction of an indole compound by photocatalysis of carbazolyl-conjugated micro-porous polymers (CMPs). The method is characterized in thatin an oxygen-containing atmosphere and water/organic mixed solvent system, the indole compound and a methylamine compound are subjected to formylation reaction under the catalytic action of iodized salt and CMPs and illumination conditions so as to obtain a 3-formaldehyde indole compound. The method has mild reaction conditions, can be implemented under room temperature and illumination conditionsand can be used for obtaining the target product in high selectivity and high yield, the reaction belongs to heterogeneous catalysis reaction, the catalyst can be recovered and recycled, and industrial production is facilitated.
Visible Light-Driven C-3 Functionalization of Indoles over Conjugated Microporous Polymers
Zhang, Weijie,Tang, Juntao,Yu, Wenguang,Huang, Qiao,Fu, Yu,Kuang, Guichao,Pan, Chunyue,Yu, Guipeng
, p. 8084 - 8091 (2018/07/30)
Metal-free and heterogeneous organic photocatalysts provide an environmentally friendly alternative to traditional metal-based catalysts. This paper reports a series of carbazole-based conjugated microporous polymers (CMPs) with tunable redox potentials and explores their photocatalytic performance with regard to C-3 formylation and thiocyanation of indoles. Conjugated polymers were synthesized through FeCl3 mediated Friedel-Crafts reactions, and their redox potentials were well regulated by simply altering the nature of the core (i.e., 1,4-dibenzyl, 1,3,5-tribenzyl, or 1,3,5-triazin-2,4,6-triyl). The resulting CMPs exhibited high surface areas, visible light absorptions, and tunable semiconductor-range band gaps. With the highest oxidative capability, CMP-CSU6 derived from 1,3,5-tri(9H-carbazol-9-yl)benzene showed the highest efficiency for C-3 formylation and thiocyanation of indoles at room temperature. Notably, the as-made catalysts can be easily recovered with good retention of photocatalytic activity and reused at least five times, suggesting good recyclability. These results are significant for constructing high-performance porous polymer catalysts with tunable photoredox potentials targeting an efficient material design for catalysis.
CuCl2/TBHP-mediated direct chlorooxidation of indoles
Wang, Huifei,Liu, Dong,Chen, Huiyu,Li, Jing,Wang, David Zhigang
supporting information, p. 7073 - 7076 (2015/08/19)
CuCl2/TBHP-mediated direct chlorooxidation of indole derivatives under simple aerobic conditions was reported, leading to facile preparations of a range of 3,3-disubstituted 3-chlorooxindoles in good yields and selectivities.
Aerobic transition-metal-free visible-light photoredox indole C-3 formylation reaction
Li, Xiang,Gu, Xiangyong,Li, Yongjuan,Li, Pixu
, p. 1897 - 1900 (2014/06/24)
An aerobic visible-light-promoted indole C-3 formylation reaction catalyzed by Rose Bengal has been developed. This transition-metal-free process employs molecular oxygen as the terminal oxidant and uses TMEDA as the one-carbon source through C-N bond cleavage. The reaction is compatible with a variety of functional groups.
Benzimidazolone as potent chymase inhibitor: Modulation of reactive metabolite formation in the hydrophobic (P1) region
Lo, Ho Yin,Nemoto, Peter A.,Kim, Jin Mi,Hao, Ming-Hong,Qian, Kevin C.,Farrow, Neil A.,Albaugh, Daniel R.,Fowler, Danielle M.,Schneiderman, Richard D.,Michael August,Martin, Leslie,Hill-Drzewi, Melissa,Pullen, Steven S.,Takahashi, Hidenori,De Lombaert, Stephane
scheme or table, p. 4533 - 4539 (2011/09/12)
A new class of chymase inhibitor featuring a benzimidazolone core with an acid side chain and a P1 hydrophobic moiety is described. Incubation of the lead compound with GSH resulted in the formation of a GSH conjugate on the benzothiophene P1 moiety. Replacement of the benzothiophene with different heterocyclic systems such as indoles and benzoisothiazole is feasible. Among the P1 replacements, benzoisothiazole prevents the formation of GSH conjugate and an in silico analysis of oxidative potentials agreed with the experimental outcome.
One-pot synthesis of highly functionalized oxindoles under swern oxidation conditions
López-Alvarado, Pilar,Steinhoff, Judith,Miranda, Sonia,Avenda?o, Carmen,Menéndez, J. Carlos
, p. 2792 - 2796 (2008/02/12)
The reaction of indole derivatives bearing a 3- or 4-hydroxyalkyl chain with dimethyl sulfoxide and oxalyl chloride under Swern conditions led to a one-pot process involving three different synthetic transformations, namely oxidation of indole to oxindole
