6180-61-6Relevant academic research and scientific papers
Selective deprotection of alkyl t-butyldimethylsilyl ethers in the presence of aryl t-butyldimethylsilyl ethers
Grieco, Paul A.,Markworth, Christopher J.
, p. 665 - 666 (1999)
Alkyl TBS ethers can be selectively cleaved in high yield in the presence of aryl TBS ethers employing either in situ generated hydrogen chloride or hydrogen iodide.
Reversible stabilization of transition-metal-binding DNA G-quadruplexes
Engelhard, David M.,Pievo, Roberta,Clever, Guido H.
, p. 12843 - 12847 (2013)
You can't top the CopperTop: Tetramolecular G-quadruplexes modified with terminal pyridine ligands exhibit metal-triggered stabilization as monitored by thermal denaturation studies, circular dichroism, and nondenaturing gel electrophoresis. Formation of the square-planar CuII(pyridine) 4 complex was confirmed by EPR measurements. The metal complexation is fully reversible by removal of the transition metal with ethylenediaminetetraacetic acid (edta). Copyright
Regiodivergent Reductive Opening of Epoxides by Catalytic Hydrogenation Promoted by a (Cyclopentadienone)iron Complex
De Vries, Johannes G.,Gandini, Tommaso,Gennari, Cesare,Jiao, Haijun,Pignataro, Luca,Stadler, Bernhard M.,Tadiello, Laura,Tin, Sergey
, p. 235 - 246 (2022/01/03)
The reductive opening of epoxides represents an attractive method for the synthesis of alcohols, but its potential application is limited by the use of stoichiometric amounts of metal hydride reducing agents (e.g., LiAlH4). For this reason, the corresponding homogeneous catalytic version with H2 is receiving increasing attention. However, investigation of this alternative has just begun, and several issues are still present, such as the use of noble metals/expensive ligands, high catalytic loading, and poor regioselectivity. Herein, we describe the use of a cheap and easy-To-handle (cyclopentadienone)iron complex (1a), previously developed by some of us, as a precatalyst for the reductive opening of epoxides with H2. While aryl epoxides smoothly reacted to afford linear alcohols, aliphatic epoxides turned out to be particularly challenging, requiring the presence of a Lewis acid cocatalyst. Remarkably, we found that it is possible to steer the regioselectivity with a careful choice of Lewis acid. A series of deuterium labeling and computational studies were run to investigate the reaction mechanism, which seems to involve more than a single pathway.
Primary Alcohols via Nickel Pentacarboxycyclopentadienyl Diamide Catalyzed Hydrosilylation of Terminal Epoxides
Lambert, Tristan H.,Steiniger, Keri A.
supporting information, p. 8013 - 8017 (2021/10/25)
The efficient and regioselective hydrosilylation of epoxides co-catalyzed by a pentacarboxycyclopentadienyl (PCCP) diamide nickel complex and Lewis acid is reported. This method allows for the reductive opening of terminal, monosubstituted epoxides to form unbranched, primary alcohols. A range of substrates including both terminal and nonterminal epoxides are shown to work, and a mechanistic rationale is provided. This work represents the first use of a PCCP derivative as a ligand for transition-metal catalysis.
Ligand-Free Copper-Catalyzed Ullmann-Type C?O Bond Formation in Non-Innocent Deep Eutectic Solvents under Aerobic Conditions
Capriati, Vito,García-álvarez, Joaquín,Marinò, Manuela,Perna, Filippo M.,Quivelli, Andrea Francesca,Vitale, Paola
, (2021/12/09)
An efficient and novel protocol was developed for a Cu-catalyzed Ullmann-type aryl alkyl ether synthesis by reacting various (hetero)aryl halides (Cl, Br, I) with alcohols as active components of environmentally benign choline chloride-based eutectic mixtures. Under optimized conditions, the reaction proceeded under mild conditions (80 °C) in air, in the absence of additional ligands, with a catalyst [CuI or CuII species] loading up to 5 mol% and K2CO3 as the base, providing the desired aryloxy derivatives in up to 98 % yield. The potential application of the methodology was demonstrated in the valorization of cheap, easily available, and naturally occurring polyols (e. g., glycerol) for the synthesis of some pharmacologically active aryloxypropanediols (Guaiphenesin, Mephenesin, and Chlorphenesin) on a 2 g scale in 70–96 % yield. Catalyst, base, and deep eutectic solvent could easily and successfully be recycled up to seven times with an E-factor as low as 5.76.
Preparation method of high-purity 3-phenoxypropyl bromide
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Paragraph 0026-0034, (2020/05/01)
The invention discloses a preparation method of aclidinium bromide key intermediate 3-phenoxypropyl bromide (formula I). The method comprises the following steps: by taking phenol and halogenated propanol as raw materials, carrying out nucleophilic substitution reaction under an alkaline condition to generate 3-phenoxy propanol, then reacting with a sulfonic acid esterification reagent to generateactive ester of 3-phenoxy propanol, refining the ester, and then reacting with a bromide of an alkali metal to generate 3-phenoxypropyl bromide. The preparation method provided by the invention has the advantages of cheap and easily available raw materials, simple operation, mild reaction conditions, no harsh reaction conditions, and high yield and purity of the obtained product, and is suitablefor industrial production.
Systems biology approaches based discovery of a small molecule inhibitor targeting both c-Met/PARP-1 and inducing cell death in breast cancer
Chen, Jie,Cheng, Lijia,Dong, Hongbo,He, Gang,Shi, Zheng,Tang, Yong,Xiong, Hang,Xu, Guangya,Yan, Xueling,Yu, Tian,Zhou, Hui
, p. 2656 - 2666 (2020/03/13)
Breast cancer is the second most common types of cancer worldwide. Molecular strategies have developed rapidly; however, novel treatments strategies with high efficacy and lower toxicity are still urgently demanded. Notably, biological networks estimated from microarray data and functional activity network analysis could be utilized to identify and validate potential targets. In this study, two microarray data (GSE13477, GSE31192) were firstly selected, and analyzed by multi-functional activity network analysis to generate the core protein-protein-interaction (PPI) network. Several potential targets were subsequently identified and c-Met and poly (ADP-ribose) polymerase-1 (PARP-1) were manually chosen as the key targets in breast cancer. Furthermore, virtual screening and molecular dynamics (MD) simulations were utilized to recognize novel c-Met/PARP-1 inhibitors in Specs products database. Three small molecules, namely, ZINC19909930, ZINC20032678 and ZINC13562414 were selected. Additionally, these compounds were synthesized, and two breast cancer cell lines, MDA-MB-231 and MCF-7 cells were used to validate our bioinformatic findings in vitro. MTT assay and Hoechst staining showed that ZINC20032678 significantly induced breast cancer cell death, which was mediated through apoptosis by flow cytometry. Furthermore, ZINC20032678 was shown to target the active sites of the both targets and recruitment of downstream apoptotic signaling pathways, eventually inducing breast cancer cell apoptosis. Collectively, our findings not only offer systems biology approaches based drug target identification, but also provide the new clues for developing novel inhibitors for future breast cancer research.
Revisiting Hydroxyalkylation of Phenols with Cyclic Carbonates
Kao, Shih-Chieh,Lin, Yi-Ching,Ryu, Ilhyong,Wu, Yen-Ku
supporting information, p. 3639 - 3644 (2019/07/10)
Described is a tetrabutylammonium fluoride-mediated hydroxyalkylation reaction of phenols with cyclic carbonates. This operationally simple method enables the synthesis of a variety of aryl β-hydroxyethyl ethers in good to excellent yields with a very small amount of catalyst loading (0.1–1 mol%). Of particular note is the efficient conversion of aromatic diols and phloroglucinol to the corresponding bis- and tris-hydroxyethylated products. To further showcase the versatility of this protocol, guaifenesin was prepared with a single step by the condensation of guaiacol and glycerol carbonate. We also developed a flow ethoxylation process permitting the continuous synthesis of multiflorol. (Figure presented.).
First example of borirane synthesis by α-olefins reaction with BCl3·SMe2 Catalyzed with (η5-C5H5)2TiCl2
Khusainova,Khafizova,Tyumkina,Dzhemilev
, p. 1517 - 1523 (2015/12/30)
New method was developed of the synthesis of 2-phenyl(alkyl, benzyl, phenoxy)-1-chloroboriranes via reaction of α-olefins with BCl3·SMe2 catalyzed by Cp2TiCl2. The method is based on the boracyclopropanes (boriranes) formation resulting from transmetallation of titanacyclopropanes arising from the reaction of α-olefins with Cp2TiCl2. The calculations were fulfilled of thermodynamic and activation parameters of possible reaction routes.
Synthesis of ionic-liquid-supported diaryliodonium salts
Kumar Muthyala, Manoj,Choudhary, Sunita,Pandey, Khima,Shelke, Ganesh M.,Jha, Mukund,Kumar, Anil
supporting information, p. 2365 - 2370 (2014/04/17)
The synthesis of ionic-liquid-supported diaryliodonium salts is described. The synthesis is simple and practical, and the ionic liquid products require no chromatographic purification. The ionic-liquid-supported diaryliodonium salts are quite stable, and they did not show any sign of decomposition or loss of reactivity, even after being stored for one month at 5 °C. The reactivity of these salts was explored in the phenylation of substituted phenols and carboxylic acids, and the corresponding diaryl ethers and aryl esters, respectively, were synthesized in good to excellent yields and with high purities.
