bluuebunny/crossref_metadata_2025 huggingface dataset:
Floating-gate type organic memory device with organic insulator film of plasma polymerized styrene
Authors: Kim Hee-Sung , Lee Boong-Joo , Shin Paik-Kyun , Ochiai Shizuyasu
Published: February 2014

Plasma polymerized styrene (ppS) thin films were prepared and used as gate insulator and tunneling layer in a floating-gate type organic memory device. To investigate feasibility of the ppS thin film for application in non-volatile organic memory, an organic thin film transistor (OTFT) and a floating-gate type organic memory device were fabricated. Current–voltage (I–V) characteristics of the OTFT and floating-gate type organic memory device were comparatively investigated, and hysteresis in the I–V characteristics of both devices was studied. A pseudo-charge-storage phenomenon was found for the ppS insulator thin film in the OTFT and floating-gate type organic memory device. The floating-gate type organic memory device revealed a reasonable hysteresis voltage of 27 V. It was confirmed that the ppS could be applied to fabricate an alternative floating-gate type organic memory device with promising memory function.
Evaluation of phonon confinement in ultrathin-film silicon-on-insulator by Raman spectroscopy
Authors: Nagata Kohki , Takei Munehisa , Ogura Atsushi , Uchida Ken
Published: February 2014

Raman spectroscopy is a practical evaluation technique for the quantum effect of phonons in a microcrystalline structure. It is very sensitive to fluctuations of crystalline potential or localized atomic geometry. Phonon confinement is observed as a broadening and desymmetrization of the Raman spectrum. However, Raman spectra also include information on crystal quality, strain, and thermal influence caused by the excitation source. Because these factors have an effect similar to that of phonon confinement on spectra, distinction of the factors is essential for accurate evaluation of the phonon confinement effect. The influence of these effects in the utrathin-film silicon-on-insulator (SOI) was investigated by Raman spectroscopy. Marked broadening and desymmetrization of Raman spectra were confirmed for the SOIs with thickness less than 5 nm. The crystalline quality and strain in the SOI layer were investigated by X-ray diffraction. We developed a precise simulation technique for phonon confinement with consideration of thermal and strain effects. By comparing the simulation with the results of Raman spectroscopy, an exact evaluation of phonon confinement effects in utrathin-film SOI was achieved.
Excellent scalability including self-heating phenomena of vertical-channel field-effect-diode type capacitor-less one transistor dynamic random access memory cell
Authors: Imamoto Takuya , Endoh Tetsuo
Published: February 2014

The scalability study and the impact of the self-heating effect (SHE) on memory operation of the bulk vertical-channel field effect diode (FED) type capacitorless one transistor (1T) dynamic random access memory (DRAM) cell are investigated via device simulator for the first time. The vertical-channel FED type 1T-DRAM cell shows the excellent hold characteristics (100 ms at 358 K of ambient temperature) with large enough read current margin (1 µA/cell) even when silicon pillar diameter (D) is scaled down from 20 to 12 nm. It is also shown that by employing the vertical-channel FED type, maximum lattice temperature in the memory cell due to SHE (

) can be suppressed to a negligible small value and only reach 300.6 from 300 K ambient temperature due to the low lateral electric field, while the vertical-channel bipolar junction transistor (BJT) type 1T-DRAM shows significant SHE (

K). Moreover, this excellent thermal characteristic can be maintained even when D is scaled down from 20 to 12 nm.
CMOS temperature sensor using a resistively degenerated common-source amplifier biased by an adjustable proportional-to-absolute-temperature voltage
Authors: Wang Ruey-Lue , Fu Chien-Cheng , Yu Chi , Hao Yi-Fan , Shi Jian-Liang , Lin Chen-Fu , Liao Hsin-Hao , Tsai Hann-Huei , Juang Ying-Zong
Published: February 2014

A high-linearity CMOS temperature sensor with pulse output is presented. The temperature core is a resistively degenerated common-source amplifier which gate is biased by a proportional-to-absolute-temperature (PTAT) voltage generator. The source resistor is made of polysilicon which resistance has a PTAT characteristic. The current flowing through the resistor exhibits a PTAT characteristic with high linearity of 99.99% at least for a temperature range from 0 to 125 °C. The PTAT voltage generator can be adjusted by a bias voltage V
b and hence the PTAT current can also be adjusted by the V
b. The PTAT current is mirrored to an added current controlled oscillator which output pulse frequencies also exhibit a PTAT characteristic. For the chip using the 0.35 µm process, the plots of measured pulse frequencies against temperature exhibit the sensitivity of 2.30 to 2.24 kHz/°C with linearity of more than 99.99% at the V
b of 1 to 1.2 V.
Evidence for a differential sea level rise between hemispheres over the twentieth century
Authors: Wöppelmann Guy , Marcos Marta , Santamaría‐Gómez Alvaro , Martín‐Míguez Belén , Bouin Marie‐Noëlle , Gravelle Médéric
Published: February 2014

Tide gauge records are the primary source of sea level information over multidecadal to century timescales. A critical issue in using this type of data to determine global climate‐related contributions to sea level change concerns the vertical motion of the land upon which the gauges are grounded. Here we use observations from the Global Positioning System for the correction of this vertical land motion. As a result, the spatial coherence in the rates of sea level change during the twentieth century is highlighted at the local and the regional scales, ultimately revealing a clearly distinct behavior between the Northern and the Southern Hemispheres with values of 2.0 mm/yr and 1.1 mm/yr, respectively. Our findings challenge the widely accepted value of global sea level rise for the twentieth century.
Meridional maps of Saturn's thermal electrons
Authors: Carbary J. F. , Rymer A. M.
Published: February 2014

All available observations (July 2004 to June 2011) made by the electron spectrometer (ELS) of the Cassini Plasma Science instrument were used to generate meridional maps of thermal electron fluxes (10–20,000 eV) separated by dayside and nightside. The maps had a spatial resolution of 1 × 1 RS (1 RS = 60,238 km), 10° resolution in pitch angle, and full ELS energy resolution. These maps indicate that electron fluxes tend to accumulate along the field lines between the L shells of ~6 and ~13 in apparent association with the flux tube of Rhea. In the vicinity of Rhea's flux tube, the electrons tend to have field‐aligned pitch angle distributions near the equator, especially between ~10 eV and ~500 eV, but can be isotropic or butterfly at different energies north or south of the equator, and there was no strong evidence of field‐aligned electron pitch angle distributions at higher latitudes. The electron fluxes display strong day‐night asymmetries in flux intensity and pitch angle distribution. However, the day‐night asymmetry observed in the ions, seen as a thicker plasma sheet on the dayside, is not observed in the electrons. Finally, the flux distributions approximately resemble those expected from propagation along field lines using conservation of the first adiabatic invariant.
Long‐term outcome of monoclonal (type 1) cryoglobulinemia
Authors: Néel Antoine , Perrin François , Decaux Olivier , Dejoie Thomas , Tessoulin Benoit , Halliez Maxime , Mahé Béatrice , Lamy Thierry , Fakhouri Fadi , Jego Patrick , Agard Christian , Vigneau Cécile , Guenet Lucienne , Grosbois Bernard , Moreau Philippe , Hamidou Mohamed
Published: February 2014

The aim of this study is to investigate long‐term outcome of symptomatic type 1 cryoglobulinemia (CG) and its determinants. Retrospective cohort study was conducted in two French University Hospitals. Patients with type 1 CG were identified using laboratory databases. Inclusion criterion was the presence of persistent symptoms of CG. Among 227 screened patients, 36 were included. Skin or vasomotor symptoms were the most frequent features (75%). Nephropathy and neuropathy occurred in 30% and 47% of cases, respectively. The underlying B cell disease (BCD) was a nonmalignant monoclonal gammopathy (NMMG) in 13 (36%) and a hematologic malignancy (HM) in 23 (64%; Waldenstrom macroglobulinemia (WM) in 12, low‐grade non‐Hodgkin lymphoma (NHL) in 6, multiple myeloma (MM) in 4, and chronic lymphocytic leukemia in 1 patient. Severe manifestations affected half the patients and were more frequent with IgG (82 vs. 30% (P = 0.006)). At last follow‐up, 64% of patients had suffered no hematologic manifestation. Potent chemotherapeutic regimens were mainly used in HM. For patients with NMMG, WM, or NHL, fludarabine or rituximab‐based regimens appeared to yield better responses. Five‐year survival rate was 82%. In multivariate analysis, mortality was significantly higher in older patients (HR: 1.17 per year [95% CI: 1.06–1.28], P = 0.001) and those with nephropathy (HR: 8.9 [95% CI: 1.9–43], P = 0.006). Kidney disease, infections, Richter's transformation, and second malignancies were important sources of morbi‐mortality. Despite its limitations, this series provide novel information regarding type 1 CG. Further studies are needed to improve its management. To date, therapeutic strategy should be tailored according to patient's characteristics (age, comorbidities, underlying BCD), and therapeutic target.Am. J. Hematol. 89:156–161, 2014. © 2013 Wiley Periodicals, Inc.
POEMS syndrome: 2014 Update on diagnosis, risk‐stratification, and management
Authors: Dispenzieri Angela
Published: February 2014

Disease overview: POEMS syndrome is a paraneoplastic syndrome due to an underlying plasma cell neoplasm. The major criteria for the syndrome are polyradiculoneuropathy, clonal plasma cell disorder (PCD), sclerotic bone lesions, elevated vascular endothelial growth factor, and the presence of Castleman disease. Minor features include organomegaly, endocrinopathy, characteristic skin changes, papilledema, extravascular volume overload, and thrombocytosis. Diagnoses are often delayed because the syndrome is rare and can be mistaken for other neurologic disorders, most commonly chronic inflammatory demyelinating polyradiculoneuropathy. POEMS syndrome should be distinguished from the Castleman disease variant of POEMS syndrome, which has no clonal PCD and typically little to no peripheral neuropathy but has several of the minor diagnostic criteria for POEMS syndrome.

Diagnosis: The diagnosis of POEMS syndrome is made with three of the major criteria, two of which must include polyradiculoneuropathy and clonal PCD, and at least one of the minor criteria.

Risk stratification: Because the pathogenesis of the syndrome is not well understood, risk stratification is limited to clinical phenotype rather than specific molecular markers. The number of clinical criteria is not prognostic, but the extent of the PCD is. Those patients with an iliac crest bone marrow biopsy that does not reveal a plasma cell clone are candidates for local radiation therapy; those with a more extensive or disseminated clone will be candidates for systemic therapy.

Risk‐adapted therapy: For those patients with a dominant sclerotic plasmacytoma, first line therapy is irradiation. Patients with diffuse sclerotic lesions or disseminated bone marrow involvement and for those who have progression of their disease 3–6 months after completing radiation therapy should receive systemic therapy. Corticosteroids are temporizing, but alkylators are the mainstay of treatment, either in the form of low dose conventional therapy or high dose with stem cell transplantation. The benefit of anti‐VEGF antibodies is conflicting. Lenalidomide shows promise with manageable toxicity. Thalidomide and bortezomib also have activity, but their benefit needs to be weighed against their risk of exacerbating the peripheral neuropathy. Prompt recognition and institution of both supportive care measures and therapy directed against the plasma cell result in the best outcomes. Am. J. Hematol. 89:214–223, 2014. © 2014 Wiley Periodicals, Inc.
Asymmetrische Hydrierung disubstituierter Furane
Authors: Wysocki Jędrzej , Ortega Nuria , Glorius Frank
Published: February 2014

Eine enantioselektive Hydrierung disubstituierter Furane in Gegenwart eines chiralen Rutheniumkatalysators mit N‐heterocyclischem Carbenliganden überführt Furane in wertvolle enantiomerenangereicherte, disubstituierte Tetrahydrofurane.
Sex or no sex: Evolutionary adaptation occurs regardless
Authors: Seidl Michael F. , Thomma Bart P. H. J.
Published: February 2014

All species continuously evolve to adapt to changing environments. The genetic variation that fosters such adaptation is caused by a plethora of mechanisms, including meiotic recombination that generates novel allelic combinations in the progeny of two parental lineages. However, a considerable number of eukaryotic species, including many fungi, do not have an apparent sexual cycle and are consequently thought to be limited in their evolutionary potential. As such organisms are expected to have reduced capability to eliminate deleterious mutations, they are often considered as evolutionary dead ends. However, inspired by recent reports we argue that such organisms can be as persistent as organisms with conventional sexual cycles through the use of other mechanisms, such as genomic rearrangements, to foster adaptation.
Biosynthesis of Phenylnannolone A, a Multidrug Resistance Reversal Agent from the Halotolerant Myxobacterium Nannocystis pusilla B150
Authors: Bouhired Sarah M. , Crüsemann Max , Almeida Celso , Weber Tilmann , Piel Jörn , Schäberle Till F. , König Gabriele M.
Published: February 2014

The myxobacterial strain Nannocystis pusilla B150 synthesizes the structurally new polyketides phenylnannolone A–C. Apart from some common volatiles and siderophores, these are the first natural products from the genus Nannocystis. Phenylnannolone A shows inhibitory activity towards the ABCB1 gene product P‐glycoprotein and reverses daunorubicin resistance in cancer cells. To decipher the biochemical reactions leading to the formation of phenylnannolone A, the putative biosynthetic genes were identified (phn1, phn2). Phn2 is a polyketide synthase (PKS) with an NRPS‐like loading module, and its domain order is consistent with the phenylnannolone A structure. The functionality and substrate selectivity of the loading module were determined by means of a γ‐18O4‐ATP pyrophosphate exchange and a phosphopantetheine ejection assay. A specific activation of cinnamic acid by the AMP‐ligase was detected. Phn1 is a putative butyryl‐CoA carboxylase (BCC), providing ethylmalonyl‐CoA for the formation of the ethyl‐substituted part of phenylnannolone A. Phn1 is the first BCC found in biosynthetic genes for an ethyl‐substituted natural compound. Biosynthesis of phenylnannolone A, putatively encoded by phn1 and phn2, thus utilizes the first biosynthetic machinery in which both a BCC and a PKS are involved.
Cytochrome P450 as Dimerization Catalyst in Diketopiperazine Alkaloid Biosynthesis
Authors: Saruwatari Takayoshi , Yagishita Fumitoshi , Mino Takashi , Noguchi Hiroshi , Hotta Kinya , Watanabe Kenji
Published: February 2014

As dimeric natural products frequently exhibit useful biological activities, identifying and understanding their mechanisms of dimerization is of great interest. One such compound is (−)‐ditryptophenaline, isolated from Aspergillus flavus, which inhibits substance P receptor for potential analgesic and anti‐inflammatory activity. Through targeted gene knockout in A. flavus and heterologous yeast gene expression, we determined for the first time the gene cluster and pathway for the biosynthesis of a dimeric diketopiperazine alkaloid. We also determined that a single cytochrome P450, DtpC, is responsible not only for pyrroloindole ring formation but also for concurrent dimerization of N‐methylphenylalanyltryptophanyl diketopiperazine monomers into a homodimeric product. Furthermore, DtpC exhibits relaxed substrate specificity, allowing the formation of two new dimeric compounds from a non‐native monomeric precursor, brevianamide F. A radical‐mediated mechanism of dimerization is proposed.
Fabclavines: Bioactive Peptide–Polyketide‐Polyamino Hybrids from Xenorhabdus
Authors: Fuchs Sebastian W. , Grundmann Florian , Kurz Michael , Kaiser Marcel , Bode Helge B.
Published: February 2014

The structure of the fabclavines—unique mixtures of nonribosomally derived peptide–polyketide hybrids connected to an unusual polyamino moiety—has been solved by detailed NMR and MS methods. These compounds have been identified in two different entomopathogenic Xenorhabdus strains, thereby leading also to the identification of the fabclavine biosynthesis gene cluster. Detailed analysis of these clusters and initial mutagenesis experiments allowed the prediction of a biosynthesis pathway in which the polyamino moiety is derived from an unusual type of fatty acid synthase that is normally involved in formation of polyunsaturated fatty acids. As fabclavines show broad‐spectrum activity against bacteria, fungi, and other eukaryotic cells, they might act as “protection factors” against all kinds of food competitors during the complex life cycle of Xenorhabdus, its nematode host, and their insect prey.
QSAR and docking studies on chalcone derivatives for antitubercular activity against M. tuberculosis H37Rv
Authors: Yadav Dharmendra Kumar , Ahmad Imran , Shukla Aparna , Khan Feroz , Negi Arvind Singh , Gupta Atul
Published: February 2014

In our prior studies, we reported some known antitubercular drugs (rifampicin and streptomycin) and newly synthesized chalcone derivatives (16–26) tested in vitro against Mycobacterium tuberculosis H37Rv strain. Most of the tested compounds were efficient antimycobacterial agents showing minimum inhibitory concentration values ranging from 3.5 to 30 µg mL−1. In the present work, a quantitative structure–activity relationship (QSAR) study has been performed on these active chalcone derivatives to correlate their chemical structures with their observed inhibiting activity against M. tuberculosis. A QSAR model that is able to correlate well the antitubercular activity with the chemical structures of active chalcone derivatives 16, 24, 25a, 25c, and 26 has been developed, which is potentially helpful in the design of novel and more potent antitubercular agents. The r2 and rCV2 of a newly derived QSAR model were 0.89 and 0.84, respectively. The QSAR study indicates that chemical properties, viz. heat of formation (kcal mol−1), lowest unoccupied molecular orbital energy (eV), and amine, hydroxyl, and methyl groups counts, correlate well with the activity. In silico screening results for oral bioavailability and absorption, distribution, metabolism, excretion, and toxicity compliance showed that compounds 25a, 25c, and 24 were found active similar to rifampicin and streptomycin. The docking study for the exploration of mechanism of action showed high binding affinity of active derivatives. Copyright © 2014 John Wiley & Sons, Ltd.
Enantioselective Synthesis and Physicochemical Properties of Libraries of 3‐Amino‐ and 3‐Amidofluoropiperidines
Authors: Orliac Aurélie , Routier Julie , Burgat Charvillon Fabienne , Sauer Wolfgang H. B. , Bombrun Agnes , Kulkarni Santosh S. , Gomez Pardo Domingo , Cossy Janine
Published: February 2014

The enantioselective syntheses of 3‐amino‐5‐fluoropiperidines and 3‐amino‐5,5‐difluoropiperidines were developed using the ring enlargement of prolinols to access libraries of 3‐amino‐ and 3‐amidofluoropiperidines. The study of the physicochemical properties revealed that fluorine atom(s) decrease(s) the pKa and modulate(s) the lipophilicity of 3‐aminopiperidines. The relative stereochemistry of the fluorine atoms with the amino groups at C3 on the piperidine core has a small effect on the pKa due to conformationnal modifications induced by fluorine atom(s). In the protonated forms, the CF bond is in an axial position due to a dipole–dipole interaction between the N−H+ and CF bonds. Predictions of the physicochemical properties using common software appeared to be limited to determine correct values of pKa and/or differences of pKa between cis‐ and trans‐3‐amino‐5‐fluoropiperidines.
The High‐Throughput Synthesis and Phase Characterisation of Amphiphiles: A Sweet Case Study
Authors: Feast George C. , Hutt Oliver E. , Mulet Xavier , Conn Charlotte E. , Drummond Calum J. , Savage G. Paul
Published: February 2014

A new method for the discovery of amphiphiles by using high‐throughput (HT) methods to synthesise and characterise a library of galactose‐ and glucose‐containing amphiphilic compounds is presented. The copper‐catalysed azide–alkyne cycloaddition (CuAAC) “click” reaction between azide‐tethered simple sugars and alkyne‐substituted hydrophobic tails was employed to synthesise a library of compounds with systematic variations in chain length and unsaturation in a 24‐vial array format. The liquid–crystalline phase behaviour was characterised in a HT manner by using synchrotron small‐angle X‐ray scattering (SSAXS). The observed structural variation with respect to chain parameters, including chain length and degree of unsaturation, is discussed, as well as hydration effects and degree of hydrogen bonding between head groups. The validity of our HT screening approach was verified by resynthesising a short‐chain glucose amphiphile. A separate phase analysis of this compound confirmed the presence of numerous lyotropic liquid–crystalline phases.
Enantioselective Cascade Michael Addition/Cyclization Reactions of 3‐Nitro‐2H‐Chromenes with 3‐Isothiocyanato Oxindoles: Efficient Synthesis of Functionalized Polycyclic Spirooxindoles
Authors: Tan Fen , Lu Liang‐Qiu , Yang Qing‐Qing , Guo Wei , Bian Qiao , Chen Jia‐Rong , Xiao Wen‐Jing
Published: February 2014

An unprecedented Zn(OTf)2‐catalyzed asymmetric Michael addition/cyclization cascade of 3‐nitro‐2H‐chromenes with 3‐isothiocyanato oxindoles has been disclosed. This transformation provides an efficient access to various synthetically important polycyclic spirooxindoles in a highly stereoselective manner under mild conditions (72–99 % yields, up to >95:5 d.r. and >99 % ee). The reaction leads to the formation of three consecutive stereocenters, including 1,3‐nonadjacent tetrasubstituted carbon stereocenters, in a single operation. A bifunctional activation model of the chiral Zn(OTf)2/bis(oxazoline) complex was proposed based on control experiments, wherein the ZnII moiety serves as a Lewis acid and the N atom of the free NH group acts as a Lewis base by a hydrogen‐bonding interaction.
Structural and Photophysical Study on Heterobimetallic Complexes with d8–d10 Interactions Supported by Carborane Ligands: Theoretical Analysis of the Emissive Behaviour
Authors: Crespo Olga , Gimeno M. Concepción , Laguna Antonio , Lehtonen Olli , Ospino Isaura , Pyykkö Pekka , Villacampa M. Dolores
Published: February 2014

Heterobimetallic complexes of formula [M{(PPh2)2C2B9H10}(S2C2B10H10)M′(PPh3)] (M=Pd, Pt; M′=Au, Ag, Cu) and [Ni{(PPh2)2C2B9H10}(S2C2B10H10)Au(PPh3)] were obtained from the reaction of [M{(PPh2)2C2B10H10}(S2C2B10H10)] (M=Pd, Pt) with [M′(PPh3)]+ (M′=Au, Ag, Cu) or by one‐pot synthesis from [(SH)2C2B10H10], (PPh2)2C2B10H10, NiCl2⋅6 H2O, and [Au(PPh3)]+. They display d8–d10 intermetallic interactions and emit red light in the solid state at 77 K. Theoretical studies on [M{(PPh2)2C2B9H10}(S2C2B10H10)Au(PPh3)] (M=Pd, Pt, Ni) attribute the luminescence to ligand (thiolate, L)‐to‐“P2‐M‐S2” (ML′) charge‐transfer (LML′CT) transitions for M=Pt and to metal (M)‐to‐“P2‐M‐S2” (ML′) charge‐transfer (MML′CT) transitions for M=Ni, Pd.
Peptide‐Based Carbohydrate Receptors
Authors: Rauschenberg Melanie , Bandaru Sateesh , Waller Mark P. , Ravoo Bart Jan
Published: February 2014

A broad spectrum of physiological processes is mediated by highly specific noncovalent interactions of carbohydrates and proteins. In a recent communication we identified several cyclic hexapeptides in a dynamic combinatorial library that interact selectively with carbohydrates with high binding constants in water. Herein, we report a detailed investigation of the noncovalent interaction of two cyclic hexapeptides (Cys‐His‐Cys (which we call HisHis) and Cys‐Tyr‐Cys (which we call TyrTyr)) with a selection of monosaccharides and disaccharides in aqueous solution. The parallel and antiparallel isomers of HisHis or TyrTyr were synthesized separately, and their interaction with monosaccharides and disaccharides in aqueous solution was studied by isothermal titration calorimetry, NMR spectroscopic titrations, and circular dichroism spectroscopy. From these measurements, we identified particularly stable complexes (Ka>1000 M−1) of the parallel isomer of HisHis with N‐acetylneuraminic acid and with methyl‐α‐D‐galactopyranoside as well as of both isomers of TyrTyr with trehalose. To gain further insight into the structure of the peptide–carbohydrate complexes, structure prediction was performed using quantum chemical methods. The calculations confirm the selectivity observed in the experiments and indicate the formation of multiple intermolecular hydrogen bonds in the most stable complexes.
Towards the Fabrication of the Top‐Contact Electrode in Molecular Junctions by Photoreduction of a Metal Precursor
Authors: Martín Santiago , Pera Gorka , Ballesteros Luz M. , Hope Adam J. , Marqués‐González Santiago , Low Paul J. , Pérez‐Murano Francesc , Nichols Richard J. , Cea Pilar
Published: February 2014

Langmuir films of 4‐{[4‐({4‐[(trimethylsilyl)ethynyl]phenyl}ethynyl)phenyl]ethynyl} benzenaminium chloride ([1 H]Cl) undergo anion metathesis when assembled on an aqueous auric acid (HAuCl4) subphase. Subsequent transfer to solid supports gives well‐formed Langmuir–Blodgett (LB) monolayers of [1 H]AuCl4 in which the trimethylsilyl group serves as the surface contacting group. Photoreduction of the aurate on these monolayers leads to the formation of metallic gold nanoislands, which were distributed over the surface of the film. Electrical properties of these nascent devices were determined by recording current–voltage (I–V) curves with conductive atomic force microscopy (c‐AFM) using the PeakForce tunneling AFM (PF‐TUNA) mode. This gives consistent sigmoidal I–V curves that are indicative of well‐behaved junctions free of metallic filaments and short circuits. The photoreduction of a metal precursor incorporated onto monomolecular films is therefore proposed as an effective method for the fabrication of molecular junctions.
From Intercalation to Groove Binding: Switching the DNA‐Binding Mode of Isostructural Transition‐Metal Complexes
Authors: Ahmad Haslina , Wragg Ashley , Cullen Will , Wombwell Claire , Meijer Anthony J. H. M. , Thomas Jim A.
Published: February 2014

The interaction with duplex DNA of a small library of structurally related complexes that all contain a d6‐metal ion coordinated to either the 2,2′:4,4′′:4′,4′′′‐quaterpyridyl ligand or its methylated derivative are reported. This library is made up of a mixture of newly synthesised and previously reported systems. Despite their structural similarities the complexes display an almost 20‐fold variation in binding affinities. Although effects due to the overall charge of the complexes are apparent, the differences in binding characteristics are deeper than this; indeed, in a number of cases, changes in overall charge have little effect on binding affinity. Intriguingly, despite interacting with DNA through unfused ring systems, although two of the complexes studied are groove binders, the majority are non‐classical intercalators. A rationale for these effects has been obtained through a combination of experimental and computational studies.
A Dithienylethene‐Based Rewritable Hydrogelator
Authors: van Herpt Jochem T. , Stuart Marc C. A. , Browne Wesley R. , Feringa Ben L.
Published: February 2014

Dithienylethene photochromic switching units have been incorporated into a hydrogelating system based on a tripeptide motif. The resulting hybrid system provided both a photochromic response and the ability to gelate water under acidic and neutral conditions. Fluorescence spectroscopy shows that the dithienylethene units are in sufficient proximity to each other to stack in gel fibers, with the tripeptide unit determining solubility. TEM measurements provided insight into the microscopic structure of the fibers formed.
Using Simple Spray Pyrolysis to Prepare Yolk–Shell‐Structured ZnO–Mn3O4 Systems with the Optimum Composition for Superior Electrochemical Properties
Authors: Choi Seung Ho , Kang Yun Chan
Published: February 2014

A spray‐pyrolysis process is introduced as an effective tool for the preparation of yolk–shell‐structured materials with electrochemical properties suitable for anode materials in Li‐ion batteries (LIBs). Yolk–shell‐structured ZnO–Mn3O4 systems with various molar ratios of the Zn and Mn components are prepared. The yolk–shell‐structured ZnO–Mn3O4 powders with a molar ratio of 1:1 of the Zn and Mn components are shown to have high capacities and good cycling performances.
Self‐Sorting of Cyclic Peptide Homodimers into a Heterodimeric Assembly Featuring an Efficient Photoinduced Intramolecular Electron‐Transfer Process
Authors: Aragay Gemma , Ventura Barbara , Guerra Arcadio , Pintre Inmaculada , Chiorboli Claudio , García‐Fandiño Rebeca , Flamigni Lucia , Granja Juan R. , Ballester Pablo
Published: February 2014

We describe the thermodynamic characterisation of the self‐sorting process experienced by two homodimers assembled by hydrogen‐bonding interactions through their cyclopeptide scaffolds and decorated with Zn–porphyrin and fullerene units into a heterodimeric assembly that contains one electron‐donor (Zn–porphyrin) and one electron‐acceptor group (fullerene). The fluorescence of the Zn–porphyrin unit is strongly quenched upon heterodimer formation. This phenomenon is demonstrated to be the result of an efficient photoinduced electron‐transfer (PET) process occurring between the Zn–porphyrin and the fullerene units of the heterodimeric system. The recombination lifetime of the charge‐separated state of the heterodimer complex is in the order of 180 ns. In solution, both homo‐ and heterodimers are present as a mixture of three regioisomers: two staggered and one eclipsed. At the concentration used for this study, the high stability constant determined for the heterodimer suggests that the eclipsed conformer is the main component in solution. The application of the bound‐state scenario allowed us to calculate that the heterodimer exists mainly as the eclipsed regioisomer (75–90 %). The attractive interaction that exists between the donor and acceptor chromophores in the heterodimeric assembly favours their arrangement in close contact. This is confirmed by the presence of charge‐transfer bands centred at 720 nm in the absorption spectrum of the heterodimer. PET occurs in approximately 75 % of the chromophores after excitation of both Zn–porphyrin and fullerene chromophores. Conversely, analogous systems, reported previously, decorated with extended tetrathiafulvalene and fullerene units showed a PET process in a significantly reduced extent (33 %). We conclude that the strength (stability constant (K)×effective molarity (EM)) of the intramolecular interaction established between the two chromophores in the Zn–porphyrin/fullerene cyclopeptide‐based heterodimers controls the regioisomeric distribution and regulates the high extent to which the PET process takes place in this system.
Switching of the Magnetocaloric Effect of MnII Glycolate by Water Molecules
Authors: Chen Yan‐Cong , Guo Fu‐Sheng , Liu Jun‐Liang , Leng Ji‐Dong , Vrábel Peter , Orendáč Martin , Prokleška Jan , Sechovský Vladimír , Tong Ming‐Liang
Published: February 2014

The transformation of MnII glycolates (glc) between the three‐dimensional coordination polymer [Mn(glc)2]n (1) and discrete mononuclear phase [Mn(glc)2(H2O)2] (2) can be reversibly switched by water molecules, which dramatically change the magnetocaloric effect (MCE) of MnII glycolates from the maximum of 6.9 J kg−1 K−1 in 1 to 60.3 J kg−1 K−1 in 2. This case example reveals that the effect of magnetic coupling on MCE plays a dominant role over that of other factors such as magnetic density for 3d‐type magnetic refrigerants.
Spectroscopic Monitoring of the Acidity of Water Films on Ru(0001): Orientation‐Specific Acidity of Adsorbed Water
Authors: Kim Youngsoon , Shin Sunghwan , Moon Eui‐Seong , Kang Heon
Published: February 2014

We examined the acid–base properties of water films adsorbed onto a Ru(0001) substrate by using surface spectroscopic methods in vacuum environments. Ammonia adsorption experiments combined with low‐energy sputtering (LES), reactive ion scattering (RIS), reflection–absorption infrared spectroscopy (RAIRS) and temperature‐programmed desorption (TPD) measurements showed that the adsorbed water is acidic enough to transfer protons to ammonia. Only the water molecules in an intact water monolayer and water clusters larger than the hexamer exhibit such acidity, whereas small clusters, a thick ice film or a partially dissociated water monolayer that contains OH, H2O and H species are not acidic. The observations indicate the orientation‐specific acidity of adsorbed water. The acidity stems from water molecules with H‐down adsorption geometry present in the monolayer. However, the dissociation of water into H and OH on the surface does not promote but rather suppresses the proton transfer to ammonia.
Rational Synthesis of Triangular Au–Ag2S Hybrid Nanoframes with Effective Photoresponses
Authors: Xu Lin , Yin Zongyou , Cao Shao‐Wen , Fan Zhanxi , Zhang Xiao , Zhang Hua , Xue Can
Published: February 2014

Triangular Au–Ag2S hybrid nanoframes were successfully synthesised by using Ag nanoprisms as templates through gold coating, etching and sulfuration. These Au–Ag2S hybrid nanoframes exhibit effective photocurrent responses for potential photoelectrochemical applications.
Mixed Adenine/Guanine Quartets with Threetrans‐a2PtII(a=NH3or MeNH2) Cross‐Links: Linkage and Rotational Isomerism, Base Pairing, and Loss of NH3
Authors: Albertí Francisca M. , Rodríguez‐Santiago Luis , Sodupe Mariona , Mirats Andrea , Kaitsiotou Helena , Sanz Miguel Pablo J. , Lippert Bernhard
Published: February 2014

Of the numerous ways in which two adenine and two guanines (N9 positions blocked in each) can be cross‐linked by three linear metal moieties such astrans‐a2PtII(with a=NH3or MeNH2) to produce open metalated purine quartets with exclusive metal coordination through N1 and N7 sites, one linkage isomer was studied in detail. The isomertrans,trans,trans‐[{Pt(NH3)2(N7‐9‐EtA‐N1)2}{Pt(MeNH2)2(N7‐9‐MeGH)}2][(ClO4)6]⋅3H2O (1) (with 9‐EtA=9‐ethyladenine and 9‐MeGH=9‐methylguanine) was crystallized from water and found to adopt a flat Z‐shape in the solid state as far as the trinuclear cation is concerned. In the presence of excess 9‐MeGH, a meander‐like construct,trans,trans,trans‐[{Pt(NH3)2(N7‐9‐EtA‐N1)2}{Pt(MeNH2)2(N7‐9‐MeGH)2}][(ClO4)6]⋅[(9‐MeGH)2]⋅7 H2O (2) is formed, in which the two extra 9‐MeGH nucleobases are hydrogen bonded to the two terminal platinated guanine ligands of1. Compound 1, and likewise the analogous complex1 a(with NH3ligands only), undergo loss of an ammonia ligand and formation of NH4+when dissolved in [D6]DMSO. From the analogy between the behavior of1and1 ait is concluded that a NH3ligand from the central Pt atom is lost. Addition of 1‐methylcytosine (1‐MeC) to such a DMSO solution reveals coordination of 1‐MeC to the central Pt. In an analogous manner, 9‐MeGH can coordinate to the central Pt in [D6]DMSO. It is proposed that the proton responsible for formation of NH4+is from one of the exocyclic amino groups of the two adenine bases, and furthermore, that this process is accompanied by a conformational change of the cation from Z‐form to U‐form. DFT calculations confirm the proposed mechanism and shed light on possible pathways of this process. Calculations show that rotational isomerism is not kinetically hindered and that it would preferably occur previous to the displacement of NH3by DMSO. This displacement is the most energetically costly step, but it is compensated by the proton transfer to NH3and formation of U(−H+) species, which exhibits an intramolecular hydrogen bond between the deprotonated N6H−of one adenine and the N6H2group of the other adenine. Finally the question is examined, how metal cross‐linking patterns in closed metallacyclic quartets containing two adenine and two guanine nucleobases influence the overall shape (square, rectangle, trapezoid) and the planarity of a metalated purine quartet.
Copper‐Catalyzed Trifluoromethylation of Internal Olefinic CH Bonds: Efficient Routes to Trifluoromethylated Tetrasubstituted Olefins and N‐Heterocycles
Authors: Mao Zhifeng , Huang Fei , Yu Haifeng , Chen Jiping , Yu Zhengkun , Xu Zhaoqing
Published: February 2014

The functionalization of internal olefins has been a challenging task in organic synthesis. Efficient CuII‐catalyzed trifluoromethylation of internal olefins, that is, α‐oxoketene dithioacetals, has been achieved by using Cu(OH)2 as a catalyst and TMSCF3 as a trifluoromethylating reagent. The push–pull effect from the polarized olefin substrates facilitates the internal olefinic CH trifluoromethylation. Cyclic and acyclic dithioalkyl α‐oxoketene acetals were used as the substrates and various substituents were tolerated. The internal olefinic CH bond cleavage was not involved in the rate‐determining step, and a mechanism that involves radicals is proposed based on a TEMPO‐quenching experiment of the trifluoromethylation reaction. Further derivatization of the resultant CF3 olefins led to multifunctionalized tetrasubstituted CF3 olefins and trifluoromethylated N‐heterocycles.
ChemInform Abstract: Theoretical Study on H3N3O3 for Solid Rocket Propellant.
Authors: Klapoetke Thomas M. , Seok Won K.
Published: February 2014

The suitability of the title molecule as potential oxidizer model for solid rocket propulsion is evaluated and predicted by HF/6‐31G* and MP4 computations.
ChemInform Abstract: Hexaaquanickel(II) Dihydrogen Hypodiphosphate.
Authors: Gjikaj Mimoza , Wu Peng , Pook Niels‐Patrick
Published: February 2014

Single crystals of the title compound are precipitated from a solution of Ni(OH)2 and H4P2O6.
ChemInform Abstract: The P4 Enantiomorph of Sr2As2O7.
Authors: Mbarek Aicha , Edhokkar Fadhila
Published: February 2014

Sr2As2O7 is prepared by solid state reaction of a 30:70 mixture of As2O5 and SrCO3 (alumina boat, 1.
ChemInform Abstract: Crystal Structures and Stability of LiCeF5 and LiThF5 at High Pressures: A Comparative Study of the Coordination Around the Ce4+ and Th4+ Ions.
Authors: Grzechnik Andrzej , Underwood Christopher C. , Kolis Joseph W. , Friese Karen
Published: February 2014

Single crystals of the title compounds are hydrothermally prepared from aqueous mixtures of ThF4 or CeF4 and LiF (autoclave, 225 °C, 1 d).
ChemInform Abstract: Tunable Blue—White—Red Photoluminescence and Long Lasting Phosphorescence Properties of a Novel Zirconate Phosphor: La2Zr2O7:Sm3+,Ti4+.
Authors: Duan Beichen , Zhang Jiachi , Liu Xue , Yuan Qi , Wang Yuhua
Published: February 2014

The title long lasting phosphorescence phosphor is prepared by solid state reaction of ZrO2, La2O3, TiO2 (0.1, 0.5, 1 mol%), and Sm2O3 (0.1, 0.5, 1, 1.5 mol%) in a H3BO3 flux (air, alumina crucible, 1673 K, 10 h).
ChemInform Abstract: A Lithium‐Rich Compound Li7Mn(BO3)3 Containing Mn2+ in Tetrahedral Coordination: A Cathode Candidate for Lithium‐Ion Batteries.
Authors: Afyon Semih , Woerle Michael , Nesper Reinhard
Published: February 2014

Crystals of the title compound are synthesized from stoichiometric mixtures of Li2O, MnO, and B2O3 (sealed Nb tube, 850 °C, 24 h).
ChemInform Abstract: Improved Capacity and Rate Capability of Fe2O3 Modified Li4Ti5O12 Anode Material.
Authors: Wang Baofeng , Cao Jie , Liu Yu , Zeng Tao , Li Lei
Published: February 2014

Spinel Li4Ti5O12/Fe2O3 composites are prepared by adding Li4Ti5O12 to a colloidal suspension of Fe(OH)3 followed by drying the resultant composite and sintering (500 °C, 5 h, N2 atmosphere).
ChemInform Abstract: Iodine—Iodine Bonding Makes Tetra(diiodine)chloride, [Cl(I2)4]‐, Planar.
Authors: Walbaum Christine , Richter Mark , Sachs Ulf , Pantenburg Ingo , Riedel Sebastian , Mudring Anja‐Verena , Meyer Gerd
Published: February 2014

Reaction of YI3 with bzc (bzc: benzo‐15‐crown‐5), NaCl, and iodine in MeOH lead to the formation of dark red to black plates of [(H5O2)(I2bzc)2] [Cl(I2)4] (I) and yellow needles or plates of [(H5O2)(I2bzc)2] [ICl2](I2bzc)2 (II).
ChemInform Abstract: Versatile Synthesis of Benzothiophenes and Benzoselenophenes by Rapid Assembly of Arylzinc Reagents, Alkynes, and Elemental Chalcogens.
Authors: Wu Bin , Yoshikai Naohiko
Published: February 2014

The combination of cobalt‐catalyzed arylzincation and copper‐mediated/catalyzed chalcogenative cyclization allows the construction of benzothiophenes and benzoselenophenes with diverse functionalities at the benzene ring, which are not readily accessible by conventional methods.
ChemInform Abstract: “Phosphite—Urea” Cooperative High‐Turnover Catalysts for the Highly Selective Bromocyclization of Homogeranylarenes.
Authors: Sawamura Yasuhiro , Nakatsuji Hidefumi , Sakakura Akira , Ishihara Kazuaki
Published: February 2014

The use of a highly active biphenol‐derived phosphite‐urea cooperative catalyst for the bromocyclization of homogeranylarenes (I) is described.
ChemInform Abstract: Rearrangement of 2‐Bromo‐1‐(bromomethyl)ethyl Esters under Basic Conditions: Scope and Mechanism.
Authors: Alliot Julien , Gravel Edmond , Doris Eric
Published: February 2014

The title reaction proceeds through formation of a transient dioxolane intermediate followed by hydrolysis with aqueous acid, which triggers ring opening and rearrangement into the final products.
ChemInform Abstract: Cupration of C2F5H: Isolation, Structure, and Synthetic Applications of [K(DMF)2][(t‐BuO)Cu(C2F5)]. Highly Efficient Pentafluoroethylation of Unactivated Aryl Bromides.
Authors: Lishchynskyi Anton , Grushin Vladimir V.
Published: February 2014

Yield of the reaction products is determined by NMR‐analysis using an internal standard.
ChemInform Abstract: Lewis Acid‐Mediated Azidolysis of 2,3‐Three Membered Heterocyclic Amines.
Authors: Righi Giuliana , Scotti Giorgio , Caruso Francesco , Rossi Miriam , Mecozzi Francesco , Antonioletti Roberto , Pelagalli Romina
Published: February 2014

The regioselectivity of the described azidolysis of aziridines and epoxides can be controlled by the use of different Lewis‐acids.
ChemInform Abstract: Overman Rearrangement of Fluorinated Allylic Alcohols as a Key Step for the Synthesis of Glycyldecylamide (GDA) Mimics.
Authors: Ramb Daniel C. , Haufe Guenter
Published: February 2014

It is shown that a vinylic fluoride substituent dramatically decelerates the reaction rate of the Overman rearrangement of acetimidates (III).
ChemInform Abstract: Stereocontrolled Cyanohydrin Ether Synthesis Through Chiral Broensted Acid‐Mediated Vinyl Ether Hydrocyanation.
Authors: Lu Chunliang , Su Xiaoge , Floreancig Paul E.
Published: February 2014

It is found that vinyl ethers can smoothly be converted into cyanohydrin ethers.
ChemInform Abstract: Enantioselective Gold(I)‐Catalyzed Vinylogous [3 + 2] Cycloaddition Between Vinyldiazoacetates and Enol Ethers
Authors: Briones John F. , Davies Huw M. L.
Published: February 2014

The diastereomeric ratio is <30:1 in all cases.
ChemInform Abstract: Cyclohexanones by Rh‐Mediated Intramolecular C—H Insertion.
Authors: Taber Douglass F. , Paquette Craig M. , Gu Peiming , Tian Weiwei
Published: February 2014

Long chain α‐aryl α‐diazo ketones cyclize efficiently to the corresponding cyclohexanones under Rh catalysis.
ChemInform Abstract: Copper Acetoacetonate [Cu(acac)2]/BINAP‐Promoted Csp3—N Bond Formation via Reductive Coupling of N‐Tosylhydrazones with Anilines.
Authors: Aziz Jessy , Brion Jean‐Daniel , Hamze Abdallah , Alami Mouad
Published: February 2014

Ketone‐ and aldehyde‐derived N‐tosylhydrazones are converted into arylamines tolerating a wide range of functional groups, primary and secondary amines including those with heteroaromatic substituents.
ChemInform Abstract: Pd‐Catalyzed Aryl C—H Imidation with Arene as the Limiting Reagent.
Authors: Boursalian Gregory B. , Ngai Ming‐Yu , Hojczyk Katarzyna N. , Ritter Tobias
Published: February 2014

In some cases complex mixtures of isomeric reaction products are observed.
ChemInform Abstract: An Easily Removable Stereo‐Dictating Group for Enantioselective Synthesis of Propargylic Amines.
Authors: Fan Wu , Ma Shengming
Published: February 2014

The title synthesis can be carried out on a gram‐scale.
ChemInform Abstract: A Recyclable Cu‐Catalyzed C—N Coupling Reaction in Water and Its Application to Synthesis of Imidazo[1,2‐a]quinoxaline.
Authors: Huang Liye , Yu Ruina , Zhu Xinhai , Wan Yiqian
Published: February 2014

The polystyrene supported pyrrole‐2‐carbohydrazide ligand is synthesized and can be successfully used for Cu‐catalyzed Ullmann‐type reactions of aryl and hetaryl halides with primary amines and imidazole.
ChemInform Abstract: Twofold Unsymmetrical C—H Functionalization of PyrDipSi‐Substituted Arenes: A General Method for the Synthesis of Substituted meta‐Halophenols.
Authors: Sarkar Dhruba , Melkonyan Ferdinand S. , Gulevich Anton V. , Gevorgyan Vladimir
Published: February 2014

Arenes having a 2‐diisopropylsilylpyridinium substituent are cleanly halogenated with NXS in ortho‐position to the silyl substituent.
ChemInform Abstract: Kinetic Resolution of Secondary Alcohols Catalyzed by Chiral Phosphoric Acids.
Authors: Harada Shingo , Kuwano Satoru , Yamaoka Yousuke , Yamada Ken‐ichi , Takasu Kiyosei
Published: February 2014

A new electronically tuned binaphthyl‐based phosphoric acid is developed, that, in contrast to conventional methods, allows the kinetic resolution of a broad range of secondary alcohols without the need of stoichiometric amounts of base.
ChemInform Abstract: Catalytic Asymmetric Insertion of Diazoesters into Aryl‐CHO Bonds: Highly Enantioselective Construction of Chiral All‐Carbon Quaternary Centers.
Authors: Gao Lizhu , Kang Byung Chul , Ryu Do Hyun
Published: February 2014

The first example of a highly enantioselective catalytic C—C insertion of diazoesters into aldehydes affords functionalized acyclic all‐carbon α‐quaternary aldehydes.
ChemInform Abstract: Palladium‐Catalyzed Suzuki—Miyaura Cross‐Coupling of α‐Halomethyl Oxime Ethers and Site‐Selective Cross‐Coupling of Dihalo Derivatives.
Authors: Noverges Barbara , Mollar Cristian , Medio‐Simon Mercedes , Asensio Gregorio
Published: February 2014

The Pd‐catalyzed cross‐coupling reaction of chloromethyl oxime ethers with a wide range of aryl‐, heteroaryl‐, and vinylboronic acids proceeds with good yields.
ChemInform Abstract: Aerobic Photooxidative Cleavage of 1,3‐Diketones to Carboxylic Acids Using 2‐Chloroanthraquinone.
Authors: Tachikawa Yuma , Cui Lei , Matsusaki Yoko , Tada Norihiro , Miura Tsuyoshi , Itoh Akichika
Published: February 2014

A direct method for the aerobic photooxidation of β‐diketones of type (I) to give benzoic acids is developed.
ChemInform Abstract: Regioselective Hydroarylations and Parallel Kinetic Resolution of Vince Lactam.
Authors: Kamlet Adam S. , Preville Cathy , Farley Kathleen A. , Piotrowski David W.
Published: February 2014

Two successful and complementary regioselective arylations are presented.
ChemInform Abstract: Regioselective Synthesis of Trichloromethyl‐Substituted Salicylates and Cyclohexenones by One‐Pot Cyclizations of 1,3‐Bis(trimethylsilyloxy)buta‐1,3‐dienes.
Authors: Langer Peter , et al. et al.
Published: February 2014

The reaction of butadienes (II) and (IV) with buten‐2‐one (I) affords trichloromethyl‐substituted salicylates (III) or corresponding cyclohexenones (VIII) depending on the type of Lewis acid employed.