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Javad Amani, Rauful Alam, Shorouk Badir, Gary A Molander
An electrophilic, imide-based, visible-light-promoted photoredox/Ni-catalyzed cross-coupling reaction for the synthesis of aliphatic ketones has been developed. This protocol proceeds through N-C(O) bond activation, made possible through the lower activation energy for metal insertion into this bond due to delocalization of the lone pair of electrons on the nitrogen by electron-withdrawing groups. The operationally simple and mild cross-coupling reaction is performed at ambient temperature and exhibits tolerance for a variety of functional groups...
April 26, 2017: Organic Letters
Jan-E Bäckvall, Jeffrey Henry, Daniels Posevins, Bin Yang, Youai Qiu
An olefin-assisted, palladium-catalyzed oxidative alkynylation of enallenes for regio- and stereoselective synthesis of substituted trienynes has been developed. The reaction shows a broad substrate scope and good tolerance for various functional groups on the allene moiety, including carboxylic acid esters, free hydroxyls, imides, and alkyl groups. Also, a wide range of ter¬minal alkynes with electron-dona¬ting and electron-withdrawing aryls, heteroaryls, alkyls, trimethylsilyl, and free hydroxyl groups are tolerated...
April 25, 2017: Chemistry: a European Journal
Taisuke Uehara, Yukinori Minoshima, Koji Sagane, Naoko Hata Sugi, Kaoru Ogawa Mitsuhashi, Noboru Yamamoto, Hiroshi Kamiyama, Kentaro Takahashi, Yoshihiko Kotake, Mai Uesugi, Akira Yokoi, Atsushi Inoue, Taku Yoshida, Miyuki Mabuchi, Akito Tanaka, Takashi Owa
Target-protein degradation is an emerging field in drug discovery and development. In particular, the substrate-receptor proteins of the cullin-ubiquitin ligase system play a key role in selective protein degradation, which is an essential component of the anti-myeloma activity of immunomodulatory drugs (IMiDs), such as lenalidomide. Here, we demonstrate that a series of anticancer sulfonamides NSC 719239 (E7820), indisulam, and NSC 339004 (chloroquinoxaline sulfonamide, CQS) induce proteasomal degradation of the U2AF-related splicing factor coactivator of activating protein-1 and estrogen receptors (CAPERα) via CRL4(DCAF15) mediated ubiquitination in human cancer cell lines...
April 24, 2017: Nature Chemical Biology
Parashuram Kallem, Martin Drobek, Anne Julbe, Erik J Vriezekolk, Reyes Mallada, Maria Pilar Pina
Liquid-induced phase-separation micromolding (LIPSμM) has been successfully used for manufacturing hierarchical porous polybenzimidazole (HPBI) microsieves (42-46% porosity, 30-40 μm thick) with a specific pore architecture (pattern of macropores: ∼9 μm in size, perforated, dispersed in a porous matrix with a 50-100 nm pore size). Using these microsieves, proton-exchange membranes were fabricated by the infiltration of a 1H-3-vinylimidazolium bis(trifluoromethanesulfonyl)imide liquid and divinylbenzene (as a cross-linker), followed by in situ UV polymerization...
April 24, 2017: ACS Applied Materials & Interfaces
Nikolai I Georgiev, Margarita D Dimitrova, Anelia Ts Mavrova, Vladimir B Bojinov
Two novel highly water-soluble fluorescence sensing 1,8-naphthalimides are synthesized and investigated. The novel compounds are designed on the "fluorophore-receptor1-spacer-receptor2" model as a molecular fluorescence probe for determination of cations and anions in 100% aqueous media. The novel probes comprising N-imide and N-phenylpiperazine or morpholine substituents are capable to operate simultaneously via ICT and PET signaling mechanism as a function of pH and to recognize selectively Cu(2+) and Hg(2+) over the other representative metal ions...
April 18, 2017: Spectrochimica Acta. Part A, Molecular and Biomolecular Spectroscopy
Shinji Sekiya, Mao Okumura, Kei Kubota, Tatsuya Nakamura, Daisuke Sekine, Seijiro Hosokawa
Stereoselective bromination of the E,E-vinylketene silyl N,O-acetal possessing a chiral auxiliary has been achieved and applied to introduction of heteroatom at γ-position of α,β-unsaturated imide. The reactions proceeded in high stereoselectivity. Total synthesis of pellasoren A, an antitumor propionate from the myxobacteriun Sorangium cellulosum, has been accomplished in short steps by this methodology and our method of reduced polypropionate synthesis.
April 21, 2017: Organic Letters
Xabier Judez, Heng Zhang, Chunmei Li, José Antonio González-Marcos, Zhi-Bin Zhou, Michel Armand, Lide Mercedes Rodriguez-Martinez
Solid polymer electrolytes (SPEs) comprising lithium bis(fluorosulfonyl)imide (Li[N(SO2F)2], LiFSI) and poly(ethylene oxide) (PEO) have been studied as electrolyte material and binder for the Li-S polymer cell. The LiFSI-based Li-S all solid polymer cell can deliver high specific discharge capacity of 800 mAh gsulfur-1 (i.e., 320 mAh gcathode-1), high areal capacity of 0.5 mAh cm-2 and relatively good rate capability. The cycling performances of Li-S polymer cell with LiFSI are significantly improved compared to with those with conventional LiTFSI (Li[N(SO2CF3)2]) salt in the polymer membrane, due to the improved stability of the Li anode/electrolyte interphases formed in the LiFSI-based SPEs...
April 13, 2017: Journal of Physical Chemistry Letters
Maria Assunta Navarra, Kanae Fujimura, Mirko Sgambetterra, Akiko Tsurumaki, Stefania Panero, Nobufumi Nakamura, Hiroyuki Ohno, Bruno Scrosati
In the present work, two ionic liquids, N-ethoxyethyl-N-methylmorpholinium bis(trifluoromethanesulfonyl)imide (M1,2O2TFSI) and N-ethoxyethyl-N-methylpiperidinium bis(trifluoromethane-sulfonyl)imide (P1,2O2TFSI) have been synthesized and compared. Fundamental relevant properties, such as thermal and electrochemical stability, density and ionic conductivity were analyzed to evaluate the effects caused by the presence of the ether bond in the side chain and/or in the organic cation ring. Upon lithium salt addition, two electrolytes suitable for lithium batteries applications were found...
April 13, 2017: ChemSusChem
Wenpeng Ni, Shimin Liu, Yuqing Fei, Yude He, Xiangyuan Ma, Liujin Lu, Youquan Deng
Considering the significant influence of oxygen-containing groups on the surface of carbon involved electrode, carbon nanotubes (CNTs) based MnO2 composite catalyst was synthesized following a facile method while using polymerized ionic liquids (PIL) as sacrifice agent. Herein, the PIL, polymerized hydrophobic 1-vinyl-3-ethylimidazolium bis ((trifluoromethyl)sulfonyl)imide, wrapped CNTs were prepared. The composite was applied to support MnO2 by the treatment of KMnO4 solution taking advantage of the reaction between PIL and KMnO4 which exclude or suppress the oxidation of CNTs, and the as-synthesized material with fewer oxygen-containing groups acted as cathode catalyst for Li-O2 batteries directly avoiding the application of binders...
April 13, 2017: ACS Applied Materials & Interfaces
Xiaoyun Chen, Qing Min Wang, Luke Bu
A two-step synthesis of polyimide reaction from dianhydride and diamine was followed by both infrared (IR) and Raman spectroscopy in situ in this case study. In the first step, the two reactants form poly(amide acid), which resulted in substantial spectral changes easily detected by both spectroscopic techniques. The reaction was found to occur rapidly and reached completion within tens of minutes at room temperature. In the second step, trimethylamine (catalyst) and acetic anhydride (dehydration agent) were added to form the five-member imide ring...
January 1, 2017: Applied Spectroscopy
B Gorska, L Timperman, M Anouti, F Béguin
The effect of low water content (<20, 150, 1000, 10 000 ppm) in triethylammonium bis[(trifluoromethyl)sulfonyl]imide - [(C2H5)3N(+)H][TFSI(-)] - protic ionic liquid (PIL) on the performance of activated carbon (AC) electrodes as well as AC/AC electrochemical capacitors (ECs) is reported. Under negative polarization, hydrogen electrosorption onto carbon is enhanced along with the increase of water content in PIL, whereas the resulting desorption peaks are shifted to lower potential values, evidencing lower sorption energy when hydrogen is stored from moisture containing PIL...
April 12, 2017: Physical Chemistry Chemical Physics: PCCP
Shuuhei Nishigaki, Miho Fukui, Haruki Sugiyama, Hidehiro Uekusa, Susumu Kawauchi, Yu Shibata, Ken Tanaka
Synthesis of alternating donor-acceptor [12] and [16]cycloparaphenylenes (CPPs) has been achieved via the rhodium-catalyzed intermolecular cross-cyclotrimerization followed by imidation and/or aromatization. These alternating donor-acceptor CPPs showed positive solvatofluorochromic properties and smaller HOMO-LUMO gaps compared with unfunctionalized CPPs, which was confirmed by the theoretical study.
April 12, 2017: Chemistry: a European Journal
Honghui Ou, Lihua Lin, Yun Zheng, Pengju Yang, Yuanxing Fang, Xinchen Wang
Tri-s-triazine-based crystalline carbon nitride nanosheets (CCNNSs) have been successfully extracted via a conventional and cost-effective sonication-centrifugation process. These CCNNSs possess a highly defined and unambiguous structure with minimal thickness, large aspect ratios, homogeneous tri-s-triazine-based units, and high crystallinity. These tri-s-triazine-based CCNNSs show significantly enhanced photocatalytic hydrogen generation activity under visible light than g-C3 N4 , poly (triazine imide)/Li(+) Cl(-) , and bulk tri-s-triazine-based crystalline carbon nitrides...
April 12, 2017: Advanced Materials
Thamires A Lima, Vitor H Paschoal, Luiz F O Faria, Mauro C C Ribeiro
Differential scanning calorimetry, X-ray diffraction, and Raman spectroscopy were used to reveal the premelting events precursors of melting of the ionic liquid triethylsulfonium bis(trifluoromethanesufonyl)imide, [S222][NTf2]. On heating the crystalline phase of [S222][NTf2], melting occurs along a sequence of at least three steps. First, the crystalline long-range order breaks down, but local order is retained. The second step is characterized by conformational freedom of the ethyl chains of cations related to premelting of nonpolar domains, and the complete melting finally occurs when anions acquire conformational freedom...
April 19, 2017: Journal of Physical Chemistry. B
Thomas Rüther, Mitsuhiro Kanakubo, Adam S Best, Kenneth R Harris
Transport properties are examined in some detail for samples of the low temperature molten salt N-propyl-N-methyl pyrrolidinium bis(fluorosulfonyl)imide [Pyr13][FSI] from two different commercial suppliers. A similar set of data is presented for two different concentrations of binary lithium-[Pyr13][FSI] salt mixtures from one supplier. A new and significantly different production process is used for the synthesis of Li[FSI] as well as the [Pyr13](+) salt used in the mixtures. Results for the viscosity, conductivity, and self-diffusion coefficients, together with the density and expansivity and apparent molar volume, are reported over the temperature range of (0 to 80) °C...
April 19, 2017: Physical Chemistry Chemical Physics: PCCP
Bárbara C Leal, Guilherme L P Aydos, Paulo A Netz, Jairton Dupont
The isomerization of estragole to trans-anethole is an important reaction and is industrially performed using an excess of NaOH or KOH in ethanol at high temperatures with very low selectivity. Simple Ru-based transition-metal complexes, under homogeneous, ionic liquid (IL)-supported (biphasic) and "solventless" conditions, can be used for this reaction. The selectivity of this reaction is more sensitive to the solvent/support used than the ligands associated with the metal catalyst. Thus, under the optimized reaction conditions, 100% conversion can be achieved in the estragole isomerization, using as little as 4 × 10(-3) mol % (40 ppm) of [RuHCl(CO)(PPh3)3] in toluene, reflecting a total turnover number (TON) of 25 000 and turnover frequencies (TOFs) of up to 500 min(-1) at 80 °C...
March 31, 2017: ACS Omega
Gilad Itchaki, Jennifer R Brown
Lenalidomide is an immunomodulatory drug (IMiD) with a unique mode of action (MOA) that may vary across disease-type. It is currently approved in multiple myeloma (MM), myelodysplastic syndrome (MDS) and mantle cell lymphoma (MCL), yet is also clinically active in a host of lymphoproliferative diseases, including chronic lymphocytic leukemia (CLL). Due to its protean effects on the immune system, lenalidomide may be particularly appealing in CLL, which is distinct in its ability to evade immune recognition and cause immunosuppression...
May 2017: Expert Opinion on Investigational Drugs
Ji-Woong Lee, Gokhan Barin, Gregory W Peterson, Jun Xu, Kristen A Colwell, Jeffrey R Long
Amic acids, consisting of carboxylic acids and amides, are often utilized as intermediates that can further undergo a dehydration-cyclization step to yield polymeric cyclic imides. Compared with imide-based materials, the presence of Brønsted acidic groups and multiple hydrogen-bond donors and acceptors in materials incorporating amic acids opens up the possibility for a variety of host-guest interactions. Here we report a facile and catalyst-free synthesis of a Brønsted acidic porous poly(amic acid) (PAA) and present its NH3 uptake properties using gas adsorption and breakthrough measurements...
April 7, 2017: ACS Applied Materials & Interfaces
Ramana Sreenivasa Rao, Chinnasamy Ramaraj Ramanathan
An efficient and alternative synthetic approach has been developed to prepare various N-(arylethyl)piperazine-2,6-diones from 4-benzenesulfonyliminodiacetic acid and primary amines using carbonyldiimidazole in the presence of a catalytic amount of DMAP at ambient temperature. Piperazine-2,6-diones are successfully transformed to pharmaceutically useful pyridopyrazines or pyrazinoisoquinolines and ene-diamides via an imide carbonyl group activation strategy using a Brønsted acid. Subsequent dehydrosulfonylation reactions of the ene-diamides, in a one pot manner, smoothly transformed them to substituted pyrazinones...
2017: Beilstein Journal of Organic Chemistry
Chuan Wan, Suochang Xu, Mary Y Hu, Ruiguo Cao, Jiangfeng Qian, Zhaohai Qin, Jun Liu, Karl T Mueller, Ji-Guang Zhang, Jian Zhi Hu
The composition of the solid electrolyte interphase (SEI) layers formed in Cu|Li cells using lithium bis(fluorosulfonyi)imide (LiFSI) and lithium bis(trifluoromethanesulfonyl)imide (LiTFSI) in 1,2-dimethoxyethane (DME) electrolytes is determined by a multinuclear solid-state MAS NMR study at high magnetic field. It is found that the "dead" metallic Li is largely reduced in the SEI layers formed in a 4 M LiFSI-DME electrolyte system compared with those formed in a 1 M LiFSI-DME electrolyte system. This finding relates directly to the safety of Li metal batteries, as one of the main safety concerns for these batteries is associated with the "dead" metallic Li formed after long term cycling...
April 4, 2017: ACS Applied Materials & Interfaces
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