22767-72-2Relevant articles and documents
Nickel-Catalyzed Alkyl-Alkyl Cross-Electrophile Coupling Reaction of 1,3-Dimesylates for the Synthesis of Alkylcyclopropanes
Chen, Pan-Pan,Hong, Xin,Jarvo, Elizabeth R.,McGinnis, Tristan M.,Sanford, Amberly B.,Thane, Taylor A.
supporting information, (2020/03/23)
Cross-electrophile coupling reactions of two Csp3-X bonds remain challenging. Herein we report an intramolecular nickel-catalyzed cross-electrophile coupling reaction of 1,3-diol derivatives. Notably, this transformation is utilized to synthesize a range of mono- and 1,2-disubstituted alkylcyclopropanes, including those derived from terpenes, steroids, and aldol products. Additionally, enantioenriched cyclopropanes are synthesized from the products of proline-catalyzed and Evans aldol reactions. A procedure for direct transformation of 1,3-diols to cyclopropanes is also described. Calculations and experimental data are consistent with a nickel-catalyzed mechanism that begins with stereoablative oxidative addition at the secondary center.
One-Pot, Tandem Wittig Hydrogenation: Formal C(sp3)-C(sp3) Bond Formation with Extensive Scope
Devlin, Rory,Jones, David J.,Mcglacken, Gerard P.
supporting information, p. 5223 - 5228 (2020/07/14)
A one-pot, tandem Wittig hydrogenation of aldehydes with stabilized ylides is reported, representing a formal C(sp3)-C(sp3) bond construction. The tandem reaction operates under mild conditions, is high yielding, and is broad in scope. Chemoselectivity for olefin reduction is observed, and the methodology is demonstrated in the synthesis of lapatinib analogues and a formal synthesis of (±)-cuspareine. Early insights suggest that the chemoselectivity observed in the reduction step is due to partial poisoning of the catalyst, after step one, thus adding to the power of the one-pot procedure.
Method for preparing organic carboxylic ester through combined catalysis of aryl bidentate phosphine ligand
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Paragraph 0049, (2020/05/29)
The invention discloses a method for preparing organic carboxylic ester by combined catalysis of an aryl bidentate phosphine ligand. The method comprises the following steps: under the action of a palladium compound/aryl bidentate phosphine ligand/acidic additive combined catalyst, carrying out a hydrogen esterification reaction on terminal olefin, carbon monoxide and alcohol so as to generate theorganic carboxylic ester with one more carbon than olefin. According to the invention, by adoption of the palladium compound/aryl bidentate phosphine ligand/acidic additive combined catalyst, good catalytic activity and selectivity for the hydrogen esterification reaction of the olefin are achieved, and olefin carbonylation to synthesize organic carboxylic ester can be efficiently catalyzed. Thearyl bidentate phosphine ligand has a rigid skeleton structure of a rigid ligand and the flexibility of a flexible ligand, so the aryl bidentate phosphine ligand has proper flexibility due to the characteristic that the aryl bidentate phosphine ligand is soft and rigid, and a most favorable coordination mode and a stable active structure in space are favorably formed. In addition, the aryl bidentate phosphine ligand has the advantages of high stability, simple and convenient synthesis method and the like; and a novel industrial technology is provided for production of organic carboxylate compounds.
Selective hydrogenation of α,β-unsaturated carbonyl compounds on silica-supported copper nanoparticles
Mendes-Burak, Jorge,Ghaffari, Behnaz,Copéret, Christophe
supporting information, p. 179 - 181 (2019/01/04)
Silica-supported copper nanoparticles prepared via surface organometallic chemistry are highly efficient for the selective hydrogenation of various α,β-unsaturated carbonyl compounds yielding the corresponding saturated esters, ketones, and aldehydes in the absence of additives. High conversions and selectivities (>99%) are obtained for most substrates upon hydrogenation at 100-150 °C and under 25 bar of H2.
Base-Free Iron Catalyzed Transfer Hydrogenation of Esters Using EtOH as Hydrogen Source
Farrar-Tobar, Ronald A.,Wozniak, Bartosz,Savini, Arianna,Hinze, Sandra,Tin, Sergey,de Vries, Johannes G.
supporting information, p. 1129 - 1133 (2019/01/04)
Herein, we report on the use of the iron pincer complex Iron-MACHO-BH, in the base-free transfer hydrogenation of esters with EtOH as a hydrogen source. More than 20 substrates including aromatic and aliphatic esters and lactones were reduced affording the desired primary alcohols and diols with moderate to excellent isolated yields. It is also possible to reduce polyesters to the diols with this method, enabling a novel way of plastic recycling. Reduction of the renewable substrate methyl levulinate proceeds to form 1,4-pentanediol directly. The yields are largely governed by the equilibrium between the alcohol and the ethyl ester.
Near-infrared fluorescence probes to detect reactive oxygen species for keloid diagnosis
Cheng, Penghui,Zhang, Jianjian,Huang, Jiaguo,Miao, Qingqing,Xu, Chenjie,Pu, Kanyi
, p. 6340 - 6347 (2018/08/12)
Development of molecular probes for the detection of reactive oxygen and nitrogen species (RONS) is important for the pathology and diagnosis of diseases. Although an abnormally high RONS level has been identified in keloids-a benign dermal tumour develop
A Dual-Modal Molecular Probe for Near-Infrared Fluorescence and Photoacoustic Imaging of Peroxynitrite
Zhang, Jianjian,Zhen, Xu,Zeng, Jianfeng,Pu, Kanyi
, p. 9301 - 9307 (2018/07/05)
Peroxynitrite (ONOO-), a reactive and short-lived biological oxidant, is closely related with many pathological conditions such as cancer. However, real-time in vivo imaging of ONOO- in tumors remains to be challenging. Herein, we de
Copper(i)-catalysed transfer hydrogenations with ammonia borane
Korytiaková, Eva,Thiel, Niklas O.,Pape, Felix,Teichert, Johannes F.
supporting information, p. 732 - 735 (2017/01/13)
Highly Z-selective alkyne transfer semihydrogenations and conjugate transfer hydrogenations of enoates can be effected by employing a readily available and air-stable copper(i)/N-heterocyclic carbene (NHC) complex, [IPrCuOH]. As an easy to handle and potentially recyclable H2 source, ammonia borane (H3NBH3) is used.
Isoprenoid Biosynthesis Inhibitors Targeting Bacterial Cell Growth
Desai, Janish,Wang, Yang,Wang, Ke,Malwal, Satish R.,Oldfield, Eric
, p. 2205 - 2215 (2016/10/22)
We synthesized potential inhibitors of farnesyl diphosphate synthase (FPPS), undecaprenyl diphosphate synthase (UPPS), or undecaprenyl diphosphate phosphatase (UPPP), and tested them in bacterial cell growth and enzyme inhibition assays. The most active compounds were found to be bisphosphonates with electron-withdrawing aryl-alkyl side chains which inhibited the growth of Gram-negative bacteria (Acinetobacter baumannii, Klebsiella pneumoniae, Escherichia coli, and Pseudomonas aeruginosa) at ~1–4 μg mL?1levels. They were found to be potent inhibitors of FPPS; cell growth was partially “rescued” by the addition of farnesol or overexpression of FPPS, and there was synergistic activity with known isoprenoid biosynthesis pathway inhibitors. Lipophilic hydroxyalkyl phosphonic acids inhibited UPPS and UPPP at micromolar levels; they were active (~2–6 μg mL?1) against Gram-positive but not Gram-negative organisms, and again exhibited synergistic activity with cell wall biosynthesis inhibitors, but only indifferent effects with other inhibitors. The results are of interest because they describe novel inhibitors of FPPS, UPPS, and UPPP with cell growth inhibitory activities as low as ~1–2 μg mL?1.
Imidazole derivatives as accelerators for ruthenium-catalyzed hydroesterification and hydrocarbamoylation of alkenes: Extensive ligand screening and mechanistic study
Konishi, Hideyuki,Muto, Takashi,Ueda, Tsuyoshi,Yamada, Yayoi,Yamaguchi, Miyuki,Manabe, Kei
, p. 836 - 845 (2015/03/14)
Imidazole derivatives are effective ligands for promoting the [Ru3(CO)12]-catalyzed hydroesterification of alkenes using formates. Extensive ligand screening was performed to identify 2-hydroxymethylated imidazole as the optimal ligand. Neither carbon monoxide gas nor a directing group was required, and the reaction also showed a wide substrate generality. The Ru-imidazole catalyst system also promoted intramolecular hydrocarbamoylation to afford lactams. A Ru-imidazole complex was unambiguously analyzed by X-ray crystallography, and it had a trinuclear structure derived from one [Ru3(CO)12] and two ligands. This complex was also successfully used for hydroesterification. The mechanism was examined in detail by using D- and 13C-labeled formates, indicating that the hydroesterification reaction proceeds by a decarbonylation-recarbonylation pathway. Effective imidazole assistant: [Ru3(CO)12]-catalyzed hydroesterification of alkenes by using formates is drastically accelerated by imidazole derivatives and exhibits a broad substrate scope for both alkenes and formates. The Ru-imidazole complex also catalyzes the intramolecular hydrocarbamoylation of alkenes.