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Hiroshi Matsui, Soichi Ito, Masayoshi Nakano
The open-shell character dependences of second hyperpolarizability γ is investigated for rectangular-shaped tetraradicaloid models such as diradical dimers, using numerically exact solutions of the extended Hubbard model. The newly-defined local diradical characters for intra- and inter-molecular interactions (referred to as yintra and yinter, respectively) are compared to conventional global ones (y0 and y1) and provide comprehensive understanding of the electronic structure of the system. The system shows two kinds of enhancements of γ components, γintra and γinter (caused, respectively, by intra- and inter-molecular diradical interactions): (i) the system with large yintra (yinter) (> ~0...
March 21, 2018: Journal of Physical Chemistry. A
Shahriar Sarhandi, Leila Zare Fekri, Esmaei Vessaly
A simple and efficient method is presented for the synthesis of benzodiazepines through the multicomponent reaction of o-phenylenediamine, various aldehydes and 5,5-dimethylcyclohexane-1,3-dione (dimedone) in the presence of the acidic bis ionic liquid 1,4-diazabicyclo[2.2.2]octanium diacetate under ultrasound irradiation. The ionic liquid used is recoverable and reusable. This procedure is simple and environmentally friendly, and offers easy work-up, mild conditions and excellent yield in a short reaction time...
March 2018: Acta Chimica Slovenica
Salah Eddine Hachani, Zelikha Necira, Djamel Eddine Mazouzi, Nadia Nebbache
Quantum chemical calculations at DFT/B3LYP level of theory with 6-31G, 6-311G, and 6-311G(d,p) basis sets were done to correlate the inhibition of mild steel corrosion in 1 M H2SO4 by four dianiline Schiff bases namely N,N'-Bis(benzylidene)-4,4'-dianiline (DAA), N,N'-Bis (benzylidene)-4,4'-methylenedianiline (MDAA), N,N' Bis(benzylidene)-4,4'-sulphonyldianiline (SDAA) and N,N'-Bis(benzylidene)-4,4'-oxydianiline (ODAA) with their electronic and structural properties. Quantum chemical parameters such as the EHOMO, ELUMO, energy gap (ΔE), dipole moment (μ), global softness (σ), and global hardness (η) were calculated and discussed to provide valuable explanations for the reactivity and selectivity of the studied inhibitors...
March 2018: Acta Chimica Slovenica
Ali Arjmandi, Hamid Reza Zare-Mehrjardi, Hadi Kargar
In this work, the carbon paste electrode (CPE) was modified using the cis-dioxo-bis[3-methoxy-2,2-dimethylpropanediamine] molybdenum(VI) complex and 1-octanaminium,N,N,N-trioctyl bromide. Using the modified electrode, the best separation of anodic peaks for ascorbic acid and dopamine was obtained in solutions with pH 5.0 and the linear range for ascorbic acid is acquired in the range from 3.0 × 10-6 to 6.0 × 10-3 M and for dopamine from 2.0 × 10-6 to 1.0 × 10-2 M. The limits of detection (S/N = 3) were 4 × 10-7 M and 5 × 10-7 M for dopamine and ascorbic acid, respectively...
March 2018: Acta Chimica Slovenica
Ramanaskanda Braveenth, Il-Ji Bae, Ji-Hun Han, Wu Qiong, Guk Seon, Kanthasamy Raagulan, Kihun Yang, Young Hee Park, Miyoung Kim, Kyu Yun Chai
Two new hole transporting materials, 2,7-bis(9,9-diphenylacridin-10(9 H )-yl)-9,9' spirobi[fluorene] (SP1) and 2,7-di(10 H -phenothiazin-10-yl)-9,9'-spirobi[fluorene] (SP2), were designed and synthesized by using the Buchwald-Hartwig coupling reaction with a high yield percentage of over 84%. Both of the materials exhibited high glass transition temperatures of over 150 °C. In order to understand the device performances, we have fabricated green phosphorescent organic light-emitting diodes (PhOLEDs) with SP1 and SP2 as hole transporting materials...
March 21, 2018: Molecules: a Journal of Synthetic Chemistry and Natural Product Chemistry
Wuxing Dong, Alison C Todd, Angelika Bröer, Sarah R Hulme, Stefan Bröer, Brian Billups
Astrocytes are glial cells that have an intimate physical and functional association with synapses in the brain. One of their main roles is to recycle the neurotransmitters glutamate and gamma-aminobutyric acid (GABA), as a component of the glutamate/GABA-glutamine cycle. They perform this function by sequestering neurotransmitters and releasing glutamine via the neutral amino acid transporter SNAT3. In this way, astrocytes regulate the availability of neurotransmitters and subsequently influence synaptic function...
March 21, 2018: International Journal of Molecular Sciences
Jessica Henoch, Armin Auch, Fatima Diab, Klaus Eichele, Hartmut Schubert, Peter Sirsch, Theresa Block, Rainer Pöttgen, Lars Wesemann
1,1'-Dilithioferrocene was reacted with 2 equiv of isopropyl (Ar*) or methyl (Ar') substituted terphenyl tin(II) chloride. Reaction product 1, carrying the bulkier terphenyl substituent Ar*, displays a bis(stannylene) structure in the solid state without formation of a tin-tin bond. Temperature-dependent solution119 Sn NMR spectroscopy, however, revealed a dynamic interplay between bis(stannylene) (100 °C) and cyclic distannene (-80 °C). In contrast to 1, the less bulky Ar' substituent results in a cyclic distannene 2...
March 21, 2018: Inorganic Chemistry
Wei Ji, Xue Zhang, Jianzhang Zhao, Ye Gao, Wei Song, Yukihiro Ozaki
A simple and ultrasensitive surface-enhanced Raman scattering (SERS) assay for heparin detection has been demonstrated based on an in situ hot spot assembly method using N,N'-bis[3,3'-(trimethylammonium)propylamine]-3,4,9,10-perylenediimide (bis-quaternized perylene dye, abbreviated as BQPER). In this assay, a BQPER probe with two positive charges is employed as both Raman reporter and electrostatic bridge to cause the aggregation of citrate-capped Ag nanoparticles (Ag NPs), resulting in a strong SERS signal due to the formation of numerous hot spots in the gaps of the aggregates...
March 21, 2018: Analyst
Igor L Fedushkin, Anton N Lukoyanov, Evgeny V Baranov
The reduction of 1,2-bis[(2,6-diisopropylphenyl)imino]acenaphthene (dpp-Bian) with an excess of La metal in the presence of iodine (dpp-Bian/I2 = 2/1) in tetrahydrofuran (thf) or dimethoxyethane (dme) affords lanthanum(III) complexes of dpp-Bian dianion: deep blue [(dpp-Bian)2- LaI(thf)2 ]2 (1, 84%) was isolated by crystallization of the product from hexane, while deep green [(dpp-Bian)LaI(dme)2 ] (2, 93%) precipitated from the reaction mixture in the course of its synthesis. A treatment of complex 1 with 0...
March 21, 2018: Inorganic Chemistry
Karsten Klauke, Dzmitry H Zaitsau, Mark Bülow, Li He, Maximilian Klopotowski, Tim-Oliver Knedel, Juri Barthel, Christoph Held, Sergey P Verevkin, Christoph Janiak
Three selenoether-functionalized ionic liquids (ILs) of N-[(phenylseleno)methylene]pyridinium (1), N-(methyl)- (2) and N-(butyl)-N'-[(phenylseleno)methylene]imidazolium (3) with bis(trifluoromethanesulfonyl)imide anions ([NTf2]) were prepared from pyridine, N-methylimidazole and N-butylimidazole with in situ obtained phenylselenomethyl chloride, followed by ion exchange to give the desired compounds. The crystal structures of the bromide and tetraphenylborate salts of the above cations (1-Br, 2-BPh4 and 3-BPh4) confirm the formation of the desired cations and indicate a multitude of different supramolecular interactions besides the dominating Coulomb interactions between the cations and anions...
March 21, 2018: Dalton Transactions: An International Journal of Inorganic Chemistry
Richard D Adams, Emmanuel J Kiprotich, Mark D Smith
Reaction of Os3(CO)10(NCMe)2 with the triosmium furyne complex Os3(CO)9(μ3,η2-C4H2O)(μ-H)2, 1 yielded the bis-triosmium complex 2 containing a bridging furyenyl ligand by CH activation at the uncoordinated C-C double bond. Heating 2 led to additional CH activation with formation of the first furdiyne C4O ligand in the complex Os3(CO)9(μ-H)2(μ3-η2-2,3-μ3-η2-4,5-C4O)Os3(CO)9(μ-H)2, 3. The furdiyne ligand in 3 was subsequently ring-opened and decarbonylated to yield products 4 and 5 containing novel bridging C3 ligands...
March 21, 2018: Chemical Communications: Chem Comm
Ibrahim Y Ahmet, Michael S Hill, Paul R Raithby, Andrew L Johnson
A family of tin(ii) guanidinate complexes of the general form [{RNC(NMe2)NR}2Sn] (R = iPr (6), Cy (7), Tol (9) and Dipp (10)) and [{tBuNC(NMe2)NtBu}Sn{NMe2}] (8) have been synthesised and isolated from the reaction of tin(ii) bis-dimethylamide and a series of carbodiimides (1-5). The cyclic poly-chalcogenide compounds [{CyNC(NMe2)NCy}2Sn{Chx}] (Ch = S, x = 4 (11); Ch = Se, x = 4 (12), and Ch = S, x = 6 (13)) with {SnChx} rings were prepared by the oxidative addition of elemental sulfur and selenium to the heteroleptic stannylene complex [{CyNC(NMe2)NCy}2Sn] (7) in THF at room temperature...
March 21, 2018: Dalton Transactions: An International Journal of Inorganic Chemistry
Hyun-Chul Kim, Seong Huh, Do Nam Lee, Youngmee Kim
Lewis basic heteroatoms orderly located inside the well-defined channels of metal-organic frameworks (MOFs) are potentially ideal active sites for selective gas sorption and catalysis. To develop functional MOFs with Lewis basic sites inside channels, a new C2h-symmetric dicarboxylate-based bridging ligand, 3,3'-(pyrazine-2,5-diyl)dibenzoic acid (3,3'-PDBA), was prepared by a Suzuki coupling reaction. Subsequently, two new Zn-MOFs containing the C2h-symmetric 3,3'-PDBA bridging ligand and two different bis(pyridyl)-based pillars, 1,2-bis(4-pyridyl)ethane (bpa) or 1,2-bis(4-pyridyl)ethylene (bpe), were prepared through a thermal reaction in N,N-dimethylformamide (DMF)...
March 21, 2018: Dalton Transactions: An International Journal of Inorganic Chemistry
Jeonghyo Lee, Sibin Wang, Miranda Callahan, Pavel Nagorny
This work describes the development of a new single-pot copper(II)-catalyzed decarboxylative Michael reaction between β-keto acids and enones, followed by in situ aldolization, which results in highly functionalized chiral and achiral cyclohexenones. The achiral version of this Robinson annulation features a hitherto unprecedented Michael reaction of β-keto acids with sterically hindered β,β'-substituted enones and provides access to all carbon quaternary stereocenter-containing cyclohexenones (11 examples, 43-83% yield)...
March 21, 2018: Organic Letters
James E M Lewis, Florian Modicom, Stephen M Goldup
We describe an operationally simple, general and high yielding active template synthesis of [2]catenanes. In addition to mechanical bond formation using a single pre-macrocycle bearing an azide and alkyne moiety, our method is also suitable for the co-macrocyclisation of readily available bis-alkyne and bis-azide co-monomers and even short alkyne/azide components which oligomerise prior to mechanical bond formation.
March 20, 2018: Journal of the American Chemical Society
Malcolm Spain, Joseph K-H Wong, Gayathri Nagalingam, James M Batten, Elinor Hortle, Stefan Oehlers, Xiao Fan Jiang, Hasini E Murage, Jack T Orford, Patrick Crisologo, James A Triccas, Peter J Rutledge, Matthew H Todd
We recently reported the discovery of non-toxic cyclam-derived compounds that are active against drug-resistant Mycobacterium tuberculosis. In this paper we report exploration of the structure-activity relationship for this class of compounds, identifying several simpler compounds with comparable activity. The most promising compound identified, possessing significantly improved water solubility, displayed high levels of bacterial clearance in an in vivo zebrafish embryo model, suggesting this compound series has promise for in vivo treatment of tuberculosis...
March 20, 2018: Journal of Medicinal Chemistry
Chengbo Tian, Shujing Zhang, Anyi Mei, Yaoguang Rong, Yue Hu, Kai Du, Miao Duan, Yusong Sheng, Pei Jiang, Gengzhao Xu, Hongwei Han
The printable mesoscopic perovskite solar cells (PMPSCs) have exhibited great attracting prospects in the energy conversion field due to their high stability and potential scalability. However, the thick perovskite film in the mesoporous layers challenge the charge transportation and increase grain boundary defects, limiting the performance of the PMPSCs. It is critical not only to improve the electric property of the perovskite film but also to passivate the charge traps to improve the device performance. Herein we synthesized a bis-adduct 2, 5-(Dimethyl ester) C60 fulleropyrrolidine (bis-DMEC60 ) via rational molecular design and incorporated it into the PMPSCs...
March 20, 2018: ACS Applied Materials & Interfaces
Yohan Ko, Yechan Kim, Chanyong Lee, Youbin Kim, Yongseok Jun
Organometallic halide perovskite solar cells (PSCs) have unique photovoltaic properties for use in next-generation solar-energy harvesting systems. The highest efficiency PSCs reached 22.1% at a lab scale of <0.1 cm2 device area. Thus, scaling up is the next step toward commercialization, but the difficulty in controlling the quality of large-area perovskite thin films remains a fundamental challenge. It has also been frequently reported that the J-V hysteresis is intensified in PSCs with areas larger than 1 cm2 ...
March 20, 2018: ACS Applied Materials & Interfaces
Cynthia Al Hageh, Majd Al Assaad, Zeinab El Masri, Nawar Samaan, Mirvat El-Sibai, Christian Khalil, Rony S Khnayzer
Copper is an earth-abundant and a biologically essential metal that offers a promising alternative to noble metals in photochemistry and photobiology. In this work, a series of sterically encumbered Cu(i) bis-phenanthroline complexes were investigated for their use in photochemotherapy (PCT). It was found that Cu(dsbtmp)2+ [dsbtmp = 2,9-disec-butyl-3,4,7,8-tetramethyl-1,10-phenanthroline] (compound 3), which possessed the longest excited state lifetime, exhibited significant in vitro photocytotoxicity on A375 (human malignant melanoma) and A549 (human lung carcinoma) cell lines...
March 20, 2018: Dalton Transactions: An International Journal of Inorganic Chemistry
Igor E Soshnikov, Nina V Semikolenova, Konstantin P Bryliakov, Artem A Antonov, Vladimir A Zakharov, Evgenii P Talsi
The nature of Ni(ii) species formed upon the activation of the Brookhart's α-diimine polymerization pre-catalyst LNiBr2 with MAO and MMAO (L = 1,4-bis-2,4,6-dimethylphenyl-2,3-dimethyl-1,4-diazabuta-1,3-diene) has been established using 1H and 13C NMR spectroscopy. The heterobinuclear ion pair [LNiII(μ-Me)2AlMe2]+[MeMAO]- is observed at the initial stage of the reaction of LNiBr2 with MAO at -40 °C, whereas the ion pair [LNiII-tBu]+[MeMMAO]- predominates at the initial stage of the reaction of LNiBr2 with MMAO under the same conditions...
March 20, 2018: Dalton Transactions: An International Journal of Inorganic Chemistry
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