bluuebunny/crossref_metadata_2025 huggingface dataset:
Student Assessment as a Political Construction: The Case of Uruguay
Authors: Benveniste Luis
Published: March 2015

This article reveals the interplay between assessment policies in Uruguay and the nature of State-societal relations. The central State has been historically a staunch defender of public education and has championed the cause of equalizing opportunities for the most disadvantaged sectors of society. The national evaluation system of student performance has been constructed as an expression of this tradition. The Uruguayan government sought to build a wide level of consensus with respect to the assessment instruments by encouraging educators to participate and buy into the assessment initiative. Moreover, the national government shifted the focus of the national evaluation from measuring schooling outcomes to addressing the social wants that condition student learning. Hence, the national evaluation has come to symbolize an agreed-upon mechanism of social accountability by which the central government upholds its responsibility for educational provision as it intervenes on behalf of impoverished communities. (Note 1)
Economic Perspectives on Investments in Teacher Quality
Authors: Plecki Margaret L.
Published: March 2015

This article reviews and critiques the ways in which researchers have used both productivity theory and human capital theory in efforts to measure the returns on investments in improving teacher quality. While studies utilizing these theories to measure investment returns provide useful insights, a critical need exists for research that advances our knowledge about the conceptual links between investments in teacher quality policies and improved student performance. The article also discusses several strategies for improving investigations regarding the returns on investments in improving teacher quality, including more refined measurement strategies, clearer conceptual frameworks, and a greater emphasis on resource re-allocation.
Moral Consideration Regarding the Arizona Tax Credit Law
Authors: Rud Anthony G.
Published: March 2015

I begin by commenting on the language used, both by the Arizona tax credit law, and by our commentators, and then turn to a discussion of a factor I believe fuels the impetus for sectarian education. I end with a consideration of questions related to the social, cognitive, and moral costs of such privatization, in contrast to a democratic commitment to education.
Technology & School Reform: A View from Both Sides of the Tracks
Authors: Warschauer Mark
Published: March 2015

A discourse of reform claims that schools must be transformed to take full advantage of computers, while a competing discourse of inequality warns that technology-enhanced reform is taking place only in wealthy schools, dooming poor and minority students to the wrong side of a digital divide. A qualitative study at an elite private school and an impoverished public school explored the relationship between technology, reform, and equality. The reforms introduced at the two schools appeared similar, but underlying differences in resources and expectations served to reinforce patterns by which the two schools channel students into different social futures.
The Social Construction of School Failure
Authors: Schuttloffel Merylann J.
Published: March 2015

A case study highlights barriers encountered by an urban school principal in implementing reforms within the context of the Kentucky Educational Reform Act. By comparing the competing expectations of Miller's (1995) five capitals and Ianneconne and Lutz's (1970) dissatisfaction theory, the case study dramatizes that Site-Based Decision-Making councils exemplify a policy decision that ignores the practical realities of distressed schools. The lack of congruence between policies and the school reality makes implementation of school reform predictably unsuccessful.
What Do Test Scores in Texas Tell Us?
Authors: Klein et al Stephen P. , Hamilton Laura , McCaffrey Daniel F. , Stecher Brian
Published: March 2015

We examine the results on the Texas Assessment of Academic Skills (TAAS), the highest-profile state testing program and one that has recorded extraordinary recent gains in math and reading scores. To investigate whether the dramatic math and reading gains on the TAAS represent actual academic progress, we have compared these gains to score changes in Texas on another test, the National Assessment of Educational Progress (NAEP). Texas students did improve significantly more on a fourth-grade NAEP math test than their counterparts nationally. But, the size of this gain was smaller than their gains on TAAS and was not present on the eighth-grade math test. The stark differences between the stories told by NAEP and TAAS are especially striking when it comes to the gap in average scores between whites and students of color. According to the NAEP results, that gap in Texas is not only very large but increasing slightly. According to TAAS scores, the gap is much smaller and decreasing greatly. Many schools are devoting a great deal of class time to highly specific TAAS preparation. While this preparation may improve TAAS scores, it may not help students develop necessary reading and math skills. Schools with relatively large percentages of minority and poor students may be doing this more than other schools. We raise serious questions about the validity of those gains, and caution against the danger of making decisions to sanction or reward students, teachers and schools on the basis of test scores that may be inflated or misleading. Finally, we suggest some steps that states can take to increase the likelihood that their test results merit public confidence and provide a sound basis for educational policy.
Segregation of Children Who Migrate to the U.S. From Puerto Rico
Authors: Laosa Luis M.
Published: March 2015

This study examined patterns of school segregation (ethnic/racial, linguistic, and socioeconomic) and other ecological characteristics of the schools that preadolescent children who migrate from Puerto Rico to the United States (New Jersey) attend in this country during the first two years following their arrival (N = 89 schools). The data show that Hispanics/Latinos are the majority of the student body in 43% of the schools; African Americans, in 30% of the schools; and European Americans, in 12% of the schools. Native speakers of Spanish are the majority of the student body in 29% of the schools. Approximately one half of the schools are in economically depressed, highly urbanized areas. Although the schools are on average large, 44% of them enroll above capacity. In most schools the majority of the student body is from economically impoverished families with low levels of parental education. There are, however, wide differences among the schools on each of these variables. Correlations show that the higher a student body's proportion of Hispanics/Latinos or native speakers of Spanish, the higher is the student body's proportion of pupils from economically impoverished households with low levels of parental education, and the higher the school's likelihood of being crowded and of being located in a poor inner-city area. Similarly, the higher a student body's proportion of African Americans, the higher is the student body's proportion of pupils from low-income families, and the higher the school's likelihood of being in a poor inner-city area. The findings are discussed with regard to implications for policy and hypotheses in need of research concerning possible consequences of school segregation for students' academic, linguistic, social, and emotional development. Also presented is a historical overview, to the present, and discussion of U.S. policies and judicial decisions concerning school segregation, with particular reference to segregation of Hispanics/Latinos.
Constructing Outcomes in Teacher Education
Authors: Cochran-Smith Marilyn
Published: March 2015

As we enter the twenty-first century, the outcomes, consequences, and results of teacher education have become critical topics in nearly all of the state and national policy debates about teacher preparation and licensure as well as in the development of many of the privately and publicly funded research agendas related to teacher and student learning. In this article, I argue that teacher education reform over the last fifty years has been driven by a series of questions about policy and practice. The question that is currently driving reform and policy in teacher education is what I refer to as "the outcomes question." This question asks how we should conceptualize and define the outcomes of teacher education for teacher learning, professional practice, and student learning, as well as how, by whom, and for what purposes these outcomes should be documented, demonstrated, and/or measured. In this article, I suggest that the outcomes question in teacher education is being conceptualized and constructed in quite different ways depending on the policy, research, and practice contexts in which the question is posed as well as on the political and professional motives of the posers. The article begins with an overview of the policy context, including those reforms and initiatives that have most influenced how outcomes are currently being constructed, debated, and enacted in teacher education. Then I identify and analyze three major "takes" on the outcomes question in teacher educationoutcomes as the long-term or general impacts of teacher education, outcomes as teacher candidates' scores on high stakes teacher tests, and outcomes as the professional performances of teacher candidates, particularly their demonstrated ability to influence student learning. For each of these approaches to outcomes, I examine underlying assumptions about teaching and schooling, the evidence and criteria used for evaluation, units of analysis, and consequences for the profession. I point out that how we construct outcomes in teacher education (including how we make the case that some outcomes matter more than others) legitimizes but also undermines particular points of view about the purposes of schooling, the nature of teaching and learning, and the role of teacher education in educational reform. In the second half of the article, I offer critique across the three constructions of outcomes, exploring the possibilities as well as the pitfalls involved in the outcomes debate. In this section, I focus on the tensions between professional consensus and critique, problems with the inputs-outputs metaphor, the need to get social justice onto the outcomes agenda, problems with the characterization of teachers as either saviors or culprits, and the connection of outcomes to educational reform strategies that are either democratic or market-driven.
The Academic Journal: Has it a Future?
Authors: Weiner Gaby
Published: March 2015

This article examines the current state of the academic journal. It does so for a number of reasons: the increasing expense of paper journals; the advent of electronic publishing; the use of publication in journals as an indicator of research quality (in addition to disseminating knowledge within a discipline) and consequent criticisms of systems of peer review and evaluation of scholarship; emergent issues of equity and access; and evidence of malpractice. These issues taken together constitute a critique of, and challenge to, the process whereby research papers become journal articles, which has in the past been viewed as unproblematic and straightforward. This paper brings together a wide range of literature in order to inform discussion about the future of the academic journal. It briefly examines the origins of the academic journal and then provides a comprehensive overview of current debates concerning how academic journals work today. In so doing, it raises questions about decisions that will need to be taken regarding the continuity or otherwise of the conventional academic journal, and how publishing practices may change in the future.
Novel insight in carbohydrate degradation during alkaline treatment
Authors: Nieminen Kaarlo , Testova Lidia , Paananen Markus , Sixta Herbert
Published: March 2015

A mathematical model is presented, in which the yield loss (YL) and the decline in polymerization of carbohydrates is comprehended. The model is applicable to the treatment of cellulose and hemicelluloses in alkaline media, and it features the actions of peeling, stopping, and alkaline hydrolysis of the polymer chains. The peeling reaction is further subdivided into primary and secondary peeling depending on whether it originates from an initial reducing end-group (REG) or from an REG created by alkaline hydrolysis. Fitting the model to experimental data provides estimates of the various reaction rate constants. When available, simultaneous observations of the YL and the decrease in chain length contribute to the evaluation of the parameters. Alternatively, if the data are limited to the YL, the obtained parameter estimates allow for a projection of the time development of chain length. The model has been applied on data from two types of experiments: soda-anthraquinone treatment of cotton linters and kraft treatment of Scots pine. It was possible to evaluate the impact of the different processes on degradation as well as the portions of polymer chains possessing active or stabilized REGs.
Wild poinsettia (Euphorbia heterophylla): an emerging weed in cotton and processing tomato in Greece
Authors: Chachalis D.
Published: March 2015

Euphorbia heterophylla (wild poinsettia) is reported as an emerging weed in cotton and processing tomato in Kopaida plain, region of Viotia, in central Greece. This is the first record of E. heterophylla in tomato crop in Greece. In a field experiment, mature plants grown under weed-free conditions produced on average 19 heads, 64 capsules, and 192 seeds per individual plant. Mature seeds exhibited no dormancy and the maximum germination (82 to 90%) occurred at temperatures from 25 to 35°C, with a drastic decline (<38%) at 15 and 40°C. Light had no significant effect on seed germination in the whole range of temperatures tested. Fully mature plants were taller than cotton, exerting strong competition. Having no light dependence for germination, seeds might have the potential to germinate and emerge from greater soil depths. This short communication summarizes information for the identification, seed germination and growth of this weed species that would support a proper weed management
Mechanism Research on Melting Loss of Coppery Tuyere Small Sleeve in Blast Furnace
Authors: Chai Yi-Fan , Zhang Jian-Liang , Ning Xiao-Jun , Wei Guang-Yun , Chen Yu-Ting
Published: March 2015

The tuyere small sleeve in blast furnace works under poor conditions. The abnormal damage of it will severely affect the performance of the blast furnace, thus it should be replaced during the damping down period. So it is of great significance that we study and reduce the burnout of tuyere small sleeve. Melting loss is one case of its burnout. This paper studied the reasons of tuyere small sleeve’s melting loss, through computational simulation and microscopic analysis of the melting section. The research shows that the temperature of coppery tuyere small sleeve is well distributed when there is no limescale in the lumen, and the temperature increases with the thickness of limescale. In addition, the interruption of circulating water does great harm to the tuyere small sleeve. The melting loss of tuyere small sleeve is caused by iron-slag erosion, with the occurrence of the melt metallurgical bonding and diffusion metallurgical combination.
Plasma-Augmented Fluidized Bed Gasification of Sub-bituminous Coal in CO2–O2 Atmospheres
Authors: Lelievre C. , Pickles C. A. , Hultgren S.
Published: March 2015

The gasification of a sub-bituminous coal using CO2–O2 gas mixtures was studied in a plasma-augmented fluidized bed gasifier. Firstly, the coal was chemically characterized and the gasification process was examined using Thermogravimetric and Differential Thermal Analysis (TGA/DTA) in CO2, O2 and at a CO2 to O2 ratio of 3 to 1. Secondly, the equilibrium gas compositions were obtained using the Gibbs free energy minimization method (HSC Chemistry®7). Thirdly, gasification tests were performed in a plasma-augmented fluidized bed and the off-gas temperatures and compositions were determined. Finally, for comparison purposes, control tests were conducted using a conventional fluidized bed coal gasifier and these results were compared to those achieved in the plasma-augmented fluidized bed gasifier. The effects of bed temperature and CO2 to O2 ratio were studied. For both gasifiers, at a given bed temperature, the off-gas compositions were in general agreement with the equilibrium values. Also, for both gasifiers, an experimental CO2 to O2 ratio of about 3 to 1 resulted in the highest syngas grade (%CO + %H2). Both higher off-gas temperatures and syngas grades could be achieved in the plasma-augmented gasifier, in comparison to the conventional gasifier. These differences were attributed to the higher bed temperatures in the plasma-augmented fluidized bed gasifier.
Rickets and vitamin D deficiency in Alaska native children
Authors: Singleton Rosalyn , Lescher Rachel , Gessner Bradford D. , Benson Matthew , Bulkow Lisa , Rosenfeld John , Thomas Timothy , Holman Robert C. , Haberling Dana , Bruce Michael , Bartholomew Michael , Tiesinga James
Published: March 2015

Rickets and vitamin D deficiency appeared to increase in Alaskan children starting in the 1990s. We evaluated the epidemiology of rickets and vitamin D deficiency in Alaska native (AN) children in 2001–2010.

We analyzed 2001–2010 visits with rickets or vitamin D deficiency diagnosis for AN and American Indian children and the general US population aged <10 years. We conducted a case-control study of AN rickets/vitamin D deficient cases and age- and region-matched controls.

In AN children, annual rickets-associated hospitalization rate (2.23/100,000 children/year) was higher than the general US rate (1.23; 95% CI 1.08–1.39). Rickets incidence increased with latitude. Rickets/vitamin D deficiency cases were more likely to have malnutrition (OR 38.1; 95% CI 4.9–294), had similar breast-feeding prevalence, and were less likely to have received vitamin D supplementation (OR 0.23; 95% CI 0.1–0.87) than controls.

Our findings highlight the importance of latitude, malnutrition, and lack of vitamin D supplementation as risk factors for rickets.
Umbilical cord plasma interferon-induced protein 10 (IP-10) and interferon-induced T-cell alpha chemoattractant (ITAC) levels are lower in women with severe preeclampsia
Authors: Chedraui Peter , Solís Emilio J. , Pérez-López Faustino R. , Schatz Fred , Kayisli Umit , Escobar Gustavo S. , Loja-Chango Rita , Hidalgo Luis , Lockwood Charles J.
Published: March 2015

Higher 1

To compare IP-10 and ITAC levels in neonatal cord blood from gestations complicated by severe preeclampsia vs. gestational age-matched controls.

Umbilical cord vessels were sampled following delivery of women with severe preeclampsia (n=30) ≥36 weeks to measure plasma IP-10 and ITAC levels and compared to corresponding controls matched for parity as well as maternal and gestational age. Chemokines were measured by specific ELISAs and expressed as pg/mL. Rho Spearman’s coefficients were calculated to establish correlations between chemokine values and various numeric variables.

Preeclamptic cases displayed significantly lower median plasma umbilical artery and vein levels of both chemokines when compared to controls (IP-10: 23.4 vs. 31.4 and 2.0 vs. 24.6 pg/mL, P<0.05; and ITAC: 2.0 vs. 13.9 and 11.9 vs. 31.6 pg/mL, P<0.05, in artery and vein, respectively). There was a significant correlation between levels of both chemokines (r

In contrast to elevated 1
Physical Education Undergraduate Students’ Colorblind Racial Ideology and Multicultural Teaching Competence
Authors: Burden, Jr. Joe W. , Hodge Samuel R. , Harrison, Jr. Louis
Published: March 2015

The purpose of this study was to analyze links between racial ideology and multicultural teaching competencies as perceived by undergraduate students in physical education teacher education (PETE) programs. Data were collected from physical education students (N = 239) across five PETE programs in the Northeastern region of the United States via a demographic questionnaire and two survey scales: (a) the Colorblind Racial Attitudes Scale (CoBRAS; Neville et al., 2000, Construction and initial validation of the color-blind racial attitudes scale (CoBRAS). Journal of Counseling Psychology, 47, 59–70) and (b) the Multicultural Teaching Competency Scale (MTCS; Spanierman et al., 2010, The multicultural teaching competencies scale (MTCS): Development and initial validation. Urban Education). Pearson product moment correlations indicated a significant negative association between scores on the MTCS’s skills dimension and participants’ colorblind racial attitudes. In addition, MANOVA results indicated significant differences in scores on the MTCS for participants at the different PETE programs in their level of perceived multicultural competence. We discuss implications of the findings and offer recommendations for teacher preparation.
A Multimarket Analysis of Inter-dependent Consumer Response Sensitivities
Authors: Voleti Sudhir
Published: March 2015

We investigate variation in aggregate consumer response sensitivities to the price, promotion and distribution elements of the marketing mix across US metropolitan markets. Primarily, three questions of research interest are examined – (i) the nature of the relationship between different aggregate response sensitivities and the implications therein, (ii) the usefulness of aggregate area-wide macroeconomic indicators such as inflation, unemployment and poverty in the context of a marketing problem, and (iii) the usefulness of geo-spatial information under a distribution-free approach. Beer category sales data across 49 major US metropolitan markets are analyzed. We find a pattern of strong inter-dependence among aggregate response sensitivities that indicates the existence of distinct, non-overlapping consumer segments. This enables a characterization of metropolitan market areas at an aggregate level. Ignoring inter-dependence mis-characterizes response sensitivity in two-thirds of the markets sampled. Further, on a standalone basis, neither area-wide economic indicators nor geo-spatial information help the analysis, but in conjunction, they vastly improve model fit (by almost 40%), explained variance (by over twice), parameter significance and consequently, insight.
Ca11InSb9, eine Zintlphase mit diskreten InSb4
9- - Anionen
Authors: Cordier Gerhard , Schäfer Herbert , Stelter Michael
Published: March 2015

Ca11InSb9 crystallizes in the orthorhombic system, space group Iba2 (No. 45), with a = 1189.4(5) pm, b = 1259.4(5) pm, c = 1673.0(7) pm. In the structure there are different kinds of anions, i.e. isolated Sb3- anions, Sb2
4- dumbbells and isolated InSb4
9- tetrahedra. The new compound belongs to the Zintlphases.
Darstellung und Kristallstruktur von Na4GeSe4: Ein neues ortho-Selenogermanat(IV)
Authors: Klepp Kurt O.
Published: March 2015

Na4GeSe4 was obtained from a stoichiometric melt of Na2Se, Ge and Se at 750 °C. It crystallizes with a new orthorhombic structure, space group Pnma, with a = 28.518(8), b - 9.447(5), c = 7.128(2) Å , Z = 8. The crystal structure was refined to a conventional R of 0.074 for 1236 reflections with I > 3 σ (I) (diffractometer data). It is characterized by discrete GeSe4
4--anions with almost regular tetrahedral geometry. Two independent anions appear in the structure, the mean Ge - Se-bond lengths are 2.345 and 2.353 Å, resp. The Na+-ions are coordinated to 4 -6 chalcogen atoms in the range 2.88-3.28 Å. The structure is composed of mixed cation-anion-slabs, 2
∞ [Na2(GeSe4)2-], which run parallel to the bc-plane and are separated from each other by corrugated 36-layers of Na+-ions.
Darstellung und Kristallstruktur des Cs2Se5 mit einer Anmerkung zum Rb2TeSe4
Authors: Kretschmann Uwe , Böttcher Peter
Published: March 2015

Cs2Se5 results from the reaction of the elements in liquid ammonia. It crystallizes with the K2S5- type structure (space group P212121; Z = 4). The cell constants are as follows: a - 7.420(2) Å , b - 18.879(4) Å , c = 7.105(1) Å. The structure is characterized by unbranched chains Se5
2- with a trans conformation. Rb2TeSe4 is synthesized from a mixture of Rb2Se3, Se, and Te (melting-reaction, 600 °C, 5 days). Its structure is isotypic with Rb2Te5 (space group C2/m, Z = 2). The cell constants are: a = 11.473(3) Å , b - 8.590(1) Å, c = 5.253(1) Å, β = 119.75(2)°. The structure contains an infinite polyanion of sixmembered rings of tellurium and selenium, connected via common vertices.
Me3CS(NH)NH2 und PhS(NH)NH2, die ersten primären Sulfinsäureimidamide
Authors: Hänssgen Dieter , Steffens Reinhard
Published: March 2015

The stepwise methanolysis of N-Lithiom ethanesulfinic acid imide amides [MeS(NSiMe3)NR']Li (l1a ,b), R' = CMe3 (a), R' = SiMe3 (b), leads to the formation of the corresponding NH compounds MeS(NSiMe3)NHR' (2a,b) and MeS(NH)NHR ' (3a), respectively. Primary sulfinic acid imide amides RS(NH)NH2 (5a,b ) are obtained for the first time in the solvolysis reaction of [RS(NSiMe3)2]Li (4a,b), R = CMe3 (a), R - Ph (b), with excess m ethanol. - Metathesis of 4b with chlorotrimethylsilane at 20 °C gives PhS(NSiMe3)N(SiMe3)2 (6). Under similar conditions 4a does not react with chlorotrimethylsilane. At higher temperatures a reductive elimination of isobutene takes place and the diaminosulfane (M e3Si)2N -S-NHSiMe3 (7) is formed.
Perfluormethyl-Element-Liganden, XXXIV* 55Mn-NMR-Untersuchungen an Zweikernkomplexen des Typs Mn2(CO)8E(CF3)2Y (E = P, As; Y = Hal und E' R; E' = S, Se, Te)
Authors: Grobe Joseph , Vetter Joachim , Rehder Dieter
Published: March 2015

Dinuclear complexes of the type {(CO)4Mn}μ-E(CF3)2, μ-Y {Mn(CO)4} (E = P, As; Y = Cl, Br, I; SR, SeR , TeR , with R varying over a wide range of inductive, mesomeric and steric properties) have been investigated by 55Mn NMR spectroscopy. The NMR signals cover the range of -415 to -1450 ppm (relative to aqueous KMnO4); half-widths are between 400 and several thousand Hz. The 55Mn - 31P one-bond coupling is usually unresolved, an exception being the complex with two P(CF3)2 bridges [J(MnP) = 152 Hz], The temperatur gradient for δ(55Mn) is 1.2 ppm/deg. Shielding of the 55Mn nucleus is discussed with respect to δ and π

bonding effects and the polarizability (electronegativity) of the bridging functions. With Y = SP(CF3)2 and SeP(CF3)2, five-ring system s with two inequivalent manganese sites are formed, which give rise to two 55Mn NMR signals, the sharper resonance for the site of higher symmetry [Mn{P(CF3)2}2] lying at -1750 ppm.
Beiträge zur Chemie des Siliciums und Germaniums, XXXVIII. Systematische Untersuchungen über die Reaktion von höheren Silanen mit Kaliumsilyl/ Contributions to the Chemistry of Silicon and Germanium, XXXVIII. Systematic Investigations on the Reaction of Higher Silanes with Potassium Silyl
Authors: Fehér Franz , Krancher Michael
Published: March 2015

Potassium disilanyl, KSi2H5, 2-potassium trisilanyl, KSiH(SiH3)2, and 2-potassium isotetrasilanyl, KSi(SiH3)3, are formed in the reactions of potassium silyl. KSiH3, with di-, tri-, n-tetra-, /so-tetra- and pentasilane, respectively. The simultaneous formation of potassium hydride can be almost completely avoided by carrying out the reactions in very diluted solution. The product mixtures formed have been analyzed by gas chromatography after reaction with benzylchloride, potassium hydride then giving toluene. A mechanism for the stepwise formation of the various higher potassium silanyls is discussed.
Das Trimetaselenoarsenit-Anion As3Se6
3– Darstellung und Struktur von [Sr(en)4]2(As3Se6)Cl/ The Trimetaselenoarsenit Anion As3 Se63 Preparation and Structure of [Sr(en)4]2 (As3 Se6)Cl
Authors: Sheldrick W. S. , Kaub J.
Published: March 2015

[Sr(en)4]2(As3Se6)Cl 1 has been prepared by the reaction of SrCl2 with As2Se3 in ethylenediamine solution under reflux and its structure established by X-ray structural analysis. 1 contains discrete cyclic As3Se6
3- anions with a six-membered As3Se3-ring in the chair conformation. A bridging ethylenediamine molecule leads to the formation of [Sr(en)4]n chains for the first of the Sr cations. In contrast, discrete Sr(en)4 units are observed for the second cation.
Synthese und Strukturuntersuchungen von Iodocupraten(I) VI. Iodocuprate(I) mit zweikernigen Anionen [CU2I4]2- und [Cu2I6]4-/ Syntheses and Structure Analyses of Iodocuprates(I) VI. Iodocuprates(I) with Dinuclear Anions [Cu2I4]2- and [Cu2I6]4-
Authors: Hartl Hans , Brüdgam Irene , Mahdjour-Hassan-Abadi F.
Published: March 2015

Bis(dipyridiniomethan)-di-μ-iodotetraiododicuprate(I), [Py2CH2]2[Cu2I6] and two modifications of bis(tetraphenylphosphonium )-di-μ-iodo-diiododicuprate(I) were obtained by reacting Cu with I2 and [Py2CH2]I2 or [PPh4]I in acetone. The crystal structures of these com pounds are built up by the cations and the binuclear anions: edge sharing Cul4-tetrahedra in [Cu2I6]4- and edge sharing, nearly trigonal planar Cul3-units in [Cu2I4]2-. Whereas the Cu2I4 anions (-A ) are centrosymmetric and almost planar, the anions (-B) are folded about the bridging I···I contact. The anions [Cu2I6] are in intimate contact with the cations via short intermolecular I···N and I···C interactions.
Notizen: Darstellung und Kristallstruktur einkerniger, paramagnetischer Pd- und Pt-Komplexe/ Preparation and Crystal Structure of Mononuclear, Paramagnetic Pd- and Pt-Complexes
Authors: Fenske Dieter , Bensmann Walter
Published: March 2015

[2,3-Bis(diphenylphosphino)m aleicanhydride]- MCl2 (M = Pd, Pt) reacts with M (PPh3)4 (M = Pd, Pt) to form paramagnetic, mononuclear complexes of Pd (Pt). It is shown by EPR , IR and X-ray examination, that the unpaired electron is delocalized on the bidentate phosphine ligand.
lodsubstituierte Eisen-Schwefel-Cluster: Neue Synthesen sowie zur Bildung und Stabilität von Fe2S2I4
2-, Fe4S4I4
2– und Fe6S6I6
2-. Die Kristallstruktur von (Et4N)6(Fe4S4l4)2Fe2S2l4 / Iodine Substituted Iron-Sulfur-Clusters: Novel Syntheses, Formation and Stability of Fe2S2I4
2-, Fe4S4I4
2- und Fe6S6I6
2-. The Crystal Structure of (Et4N)6(Fe4S4l4)2Fe2S2l4
Authors: Saak Wolfgang , Pohl Siegfried
Published: March 2015

Fe4S4I4
2- has been prepared in tetrahydrofuran (THF) solution by the reaction of Fe, S8, I2, and Me3NCH2Ph+TI-, and isolated as black, fairly air-stable crystals of (Me3NCH2Ph)2Fe4S4I4 (1) in nearly quantitative yield. 1 reacts with iron and iodine or with elemental sulfur and Fel2 in CH2Cl2 solution to form Fe6S6I6
2- which was isolated as black crystals of (Me3NCH2Ph)2Fe6S6I6 (5). In THF solution Fe6S6I6
2- is converted to Fe4S4I4
2- which was isolated as Fe(THF)6Fe4S4I4·4 THF (3). Evidence is presented for an equilibrium between Fe2S2I4
2- and Fe4S4I4
2-, Fel4
2- and sulfur when iron, sulfur, iodine and Et4N+I- react (with the required stoichiometry) to form Fe2S2I4
2- in CH2Cl2 solution. From this solution (Et4N)6(Fe4S4I4)2Fe2S2I4 (6 ) crystallizes as black needles (tetragonal, P42bc, a = 2467.9, b = 1653.8 pm, Z = 4). Crystals of 6 consist of the discrete anions Fe4S4I4
2- and Fe2S2I4
2- and Et4N+ cations. The [Fe4S4]2+ core does not exhibit the usually observed core distortion.

This clearly demonstrates that additional ligands (THF, CH3CN, iodide ions etc.) strongly reduce the stability of iodine substituted Fe/S clusters (except [Fe4S4]2+ cores!).

The biological relevance of the observed rearrangements is discussed.
Beiträge zur Chemie der Schwefelhalogenide, 9 [1]. Trifhiormethyldichlorsulfonium(IV)-hexafluoroarsenat(V) / Contributions to the Chemistry of Sulfur Halides, 9 [1] Trifluoromethyldichlorosulfonium(IV) Hexafluoroarsenate(V )
Authors: Minkwitz Rolf , Naß Ulrike , Radünz Armin , Preut Hans
Published: March 2015

The synthesis of CF3SCl2
+AsF6
- is reported. The sulfonium salt is characterised by IR, Raman, 19F and 13C NMR spectroscopy. The vibrational assignment is based on a Cs model for the cation and assisted by a normal coordinate analysis. The crystal structure has been determined from three-dimensional diffractometer data at -133 K. The structural data for the cation are: C-F = 128.8(5) pm, C-S = 197,8(3) pm, S-Cl = 195,9(1) pm and F-C-F = 111,8(3)°, Cl-S-Cl = 104,22(5)°, C-S-Cl = 99,8(1)°.
Metallkomplexe mit biologisch wichtigen Liganden, XLI [1]. Platin(II)- und Cobalt(III)-Komplexe von Monosaccharid-Derivaten mit Metall-Schwefel- und Metall-Kohlenstoff-Bindungen / Metal Complexes with Biologically Important Ligands, XLI [1]. Platinum(II) and Cobalt(III) Complexes of Monosaccharide Derivatives with Metal-Sulfur and Metal-Carbon Bonds
Authors: Nagel Yvonne , Beck Wolfgang
Published: March 2015

The reaction of bis(2,3,4,6-tetra-0-acetyl-β-D-glucopyranosyl)disulfide with (Ph3P)2Pt(C2H4) gives cis-di(2,3,4,6-tetra-0-acetyl-l-mercapto-β-D-glucopyranosid)bis(triphenylphosphane)platinum (II). A dithiocarbimato complex (Ph3P)2Pt(S2CNR) has been isolated from cis-(Ph3P)2PtCl2, CS2 and 1-0-Methyl-2-amino-2-deoxy-4,6-benzyliden-α,β-D-glucopyranoside. Metal complexes with metal-carbon bonds have been prepared by oxidative addition of monosaccharide halides to (Ph3P)2Pt(C2H4) or to cobalt(I) cobaloxime, respectively. From the reaction of (Ph3P)2Pt(C2H4) with 2,3,4,6 -Tetra-O-acetyl-α-D-glucopyranosyl-bromide the anomers trans-(α- and β-glucopyranosyl) Pt(PPh3)2Br have been obtained. This indicates a radical reaction.
Gehinderte Ligandbewegungen in Übergangsmetallkomplexen, XXVIII [1] Photochemische C–H-Aktivierung an 1,3,5-Cycloheptatrien durch Rhenium(O) / Hindered Ligand Movements in Transition Metal Complexes, XXVIII [1] Photochemical C–H-Activation at 1,3,5-Cycloheptatriene by Rhenium(O)
Authors: Kreiter Cornelius G. , Franzreb Karl Heinz , Michels Wolfgang , Schubert Ulrich , Ackermann Klaus
Published: March 2015

Decacarbonyl-dirhenium(O) (1) photochemically cleaves C-H-bonds in 1,3,5-cycloheptatriene (2 ) and forms two isomeric Re2(CO)8(μ-H)(μ-η2:1-cycloheptatrienyl) complexes (3, 4). In addition Re(CO)3(η5-cycloheptatrienyl) (5) and Re(CO)3(η5-cycloheptadienyl) (6) are obtained. The complexes 3 and 4 show temperature dependent 1H NMR spectra due to hindered ligand movements of the cycloheptatrienyl bridges with activation barriers of ⊿G≠
207 = 39.9±2 kJ mol-1 and ⊿G≠
255 = 48.0±2 kJ mol-1. 3 and 4 achieve in a thermal reaction an equilibrium with populations of 0.03 and 0.97 at 350 K with ⊿G≠
350 - 96.5±5 kJ mol-1. The molecular structure of the more stable isomer, Re2(CO)8(μ-H)(μ-η2:1-1 ,3,5-cycloheptatrien-2-yl) (4 ) was determined by X-ray structure analysis.
Substitution Effects on Electronic Structure of Thiophene
Authors: Bajić Miroslav , Humski Krešimir , Klasinc Leo , Ruščić Branko
Published: March 2015

The He (I) photoelectron (PE) spectra of the following methoxy (-MeO) and nitro (-NO2) thiophenes: 2-MeO, 3-MeO, 2,5-di-MeO, 2-NO2, 3-NO2, 2,4 -di-NO2 and 2,5 -di-NO2 have been recorded and their electronic structure is discussed in terms of inductive and mesomeric effects of substituent on the electronic energy levels of thiophene.
Stoffwechselprodukte von Mikroorganismen, XXXI [1]. Duricaulinsäure, ein neuer Naturstoff vom Phthalimidin-Typ aus Aspergillus duricaulis / Metabolie Products of Microorganisms, XXXI [1]. Duricaulic Acid, a New Natural Product of the Phthalim idine Type from Aspergillus duricaulis
Authors: Achenbach Hans , Mühlenfeld Andreas , Kohl Werner , Brillinger Gert-Ulf
Published: March 2015

Duricaulic acid (1), a new nitrogen containing metabolite was isolated from Aspergillus

duricaulis and its structure established. 1H and 13C NMR of some phthalimidines are discussed.
AsPh4[W(O)Cl3(HN3S2)]; Synthese, IR-Spektrum und Kristallstruktur / AsPh4[W(O)Cl3(HN3S2)]; Synthesis, IR Spectrum and Crystal Structure
Authors: Conradi Elke , Wadle Heribert , Müller Ulrich , Dehnicke Kurt
Published: March 2015

Violet crystals of AsPh4[W(O)Cl3(HN3S2)] were obtained by partial hydrolysis of AsPh4[WCl4(N3S2)] in a saturated solution in CH2Cl2/CCl4. Its IR spectrum is reported. The crystal structure was determined by X-ray diffraction (2284 independent observed reflexions, R = 0.041). Crystal data: triclinic, space group P1̄, Z = 2, a = 812.2, b = 1268.4, c = 1343.9 pm, α = 88.58, β = 82.04 and γ = 88.26°. The compound consists of AsPh4
⊕ cations and [W(O)Cl3(HN3S2)⊖ anions in which the tungsten atoms have a distorted octahedral coordination with one oxo-ligand (171 pm), three chlorine atoms and two nitrogen atoms of the planar (HN3S7)2⊖ ligand. The WN bond lengths are 183 and 226 pm; the longer WN bond is due to the hydrogen atom attached to its N atom and to the trans influence of the oxo group. The crystal packing corresponds to one of the types frequently found among tetraphenylphosphonium compounds with cations stacked to parallel columns.
NMR-Untersuchungen an 3,3-Difluor-2-ethyI-1,1,2-tris(diethoxyphosphoryI)-cyclopropan / NMR Investigation of 3,3-Difluoro-2-ethyl-1,1,2-tris(diethoxyphosphoryl)cyclopropane
Authors: Heckmann Gernot , Fluck Ekkehard , Svara Jürgen
Published: March 2015

The 19F, 31P and 13C NMR spectra in double and triple resonance mode and the temperature dependence of the NMR parameters of the title compound are discussed in detail. The rotational behavior of the phosphoryl groups is described; two of these groups show equal barriers to rotation of 75 kJ mol-1, the third one is rotating freely at room temperature.
Determination of the Enantiomeric Excess of Horner Phosphines by 13C NMR Spectroscopy. A 13C and 31P NMR Study of the Diastereomeric Complexes Formed with [η3-(+)(1R,5R )-Pinenyl]nickel Bromide Dimer
Authors: Mynott Richard , Richter Wolf Jürgen , Wilke Günther
Published: March 2015

The 13C and 31P NMR data of the Horner phosphines PRR′R″ [R = Me. R′ = t-Bu, R'″ = Ph (2) or i-Pr (4)] and their diastereomeric 1:1 adducts with [η3-(+)(1 R, 5 R)-pinenyI]nickel bromide dimer (3) and (5), respectively, are reported. It is shown that the optical purities of the phosphines can be deduced easily from the NMR spectra. Not only are these values in very good agreement with those obtained from optical rotatory data but they are also obtained much more conveniently.
Cyanothioacetamide in Heterocyclic Synthesis: A New Approach for the Synthesis of 2-Pyridothione and 2-Pyridazinothione Derivatives
Authors: Mohareb R. M. , Fahmy S. M.
Published: March 2015

Cyanothioacetamide (1) undergoes self condensation to give 4,6-diamino-3-cyano-2-pyrido-thione (2). The latter was utilised in synthesis of pyrido[2,3-c]pyrazole, pyrido[2,3-d]pyrim idine, bis-(pyridothione derivatives) through reaction with hydrazine hydrate, ethoxycarbonyl isothio-cyanate and cinnamonitrile derivatives. Also 1 undergoes self dimerisation to give 13, the latter form the pyridazine derivative on coupling with benzenediazonium chloride.
Chemilumineszenz von Photoprodukten polyzyklischer aromatischer Kohlenwasserstoffe und deren Carbonylverbindungen / Chemiluminescence of Photoproducts of Polycyclic Aromatic Hydrocarbons and their Carbonyl Compounds
Authors: Stauff Joachim , Stärk Gerhard
Published: March 2015

During photooxidation of polycyclic aromatic hydrocarbons (PAH) products can be formed which develop chemiluminescence on treatment with bases. Flash photolysis experiments show that this is the case only after previous formation of cation radicals, e.g. in the presence of CCl4 as solvent or of e-acceptors in aprotic solvents. These radicals react with oxygen to peroxy-radicals which can combine to several kinds of peroxides. Primary and secondary peroxides are the sources of chemiluminescent activity.

Chemiluminescent peroxides can also be obtained by irradiation of PA H carbonyl com pounds in protic solvents under nitrogen. It is assumed that two excited CO groups combine exceptionally with their O-atom s thus creating a peroxide bond. 24 aromatic aldehydes, ketones, dicarboxylic acid anhydrides and coumarines develop chemiluminescence after illumination with wavelengths ≥ 320 nm with intensities varying 4 magnitudes of order.

The sensitivity of the photochemiluminescent method is sufficient to detect amounts of PA H and their CO derivatives in the ppb to ppm range.
In the Search for New Anticancer Drugs, XVI Selective Protection and Deprotection of Primary Amino Groups in Spermine, Spermidine and Other Polyamines
Authors: Sosnovsky George , Lukszo Jan
Published: March 2015

Spermidine, spermine and other polyamines 1-5 were selectively protected at the terminal primary amino functions without affecting the secondary amino groups using N-ethoxycarbonyl-phthalimide (15), the Nefkens’ reagent. Three representative products, 17, 18 and 20, readily underwent acylation at the secondary amino nitrogen to give the corresponding compounds 21-26. Selective deprotection of two representative samples 22 and 25 at the primary amino function by hydrazinolysis yielded the corresponding derivatives 27 and 28 with free primary amino groups.

In summary, the application of Nefkens’ reagent for the terminal protection of primary amino groups in various polyamines results in a simple, efficient and selective one-step procedure using commercially available reagents.
Reaktive E=C(p-p)π-Systeme, VI [1] Reaktionen des Phosphaalkens F3CP=CF2 mit H-aciden Verbindungen/Reactive E = C(p-p)π-Systems, VI [1] Reactions of the Phosphaalkene F3CP = CF2 with H Acidic Compounds
Authors: Grobe Joseph , Le Van Duc , Nientiedt Jürgen
Published: March 2015

The reactions o f the perfluorophosphaalkene F3CP = CF2 (1) with HX compounds proceed via addition to the PC double bond yielding either secondary phosphanes F3CP(H)CF2X (X = OH, OR, NR2, PMe2) or PX derivatives F3CP(X)CF2H (X = Cl, Br, SMe, SeMe, AsMe2). The rate of reaction with H2O is strongly pH-dependent, but only at pH > 13 the opposite direction of addition is observed. Similar results are obtained for the addition of alcohols, for which the presence of OR- results in two effects: (i) Reversion of the addition direction to yield F3CP(OR)CF2H; (ii) HF elimination from F3CP(H)CF2OR to give substituted phosphaalkenes. With strong bases HNR2, the addition is followed immediately by HF elimination producing the surprisingly stable phosphaalkenes F3CP = C(F)NR2 (R = Me, Et). Secondary phosphanes of the type F3CP(H)CF2X (X = OMe, OEt, PMe2) are found to be suitable precursors for the preparation of novel heterosubstituted derivatives of 1 by elimination of HF with NMe3. New compounds were characterized by NMR, MS, GC/MS and GC/IR measurements.
Transanulare Wechselwirkung bei [m.n]Phanen, 32 [1]: Modelle für Amin-Aromaten-Exciplexe: [2](1,4)Anthraceno[2](2,6)pyridinophan-1,13-dien/Transanular Interaction in [m .n]Phanes, 32 [1]: Models for Amine-Arene-Exciplexes: [2](1,4)Anthraceno[2](2,6)pyridinophan-1,13-dien
Authors: Haenel Matthias W. , Lintner Birgit , Schweitzer Dieter
Published: March 2015

The [2](1,4)Anthraceno[2](2,6)pyridinophan-1,13-dien (5) and the corresponding [2.2]phane (7) were synthesized as models for exciplexes. The dithia[3.3]phanes(9) and (11) were prepared by cyclisation of the dithiols 13 and 16 with the dibromide 19. Oxidation of 9 to the disulfone 10 and vapour phase pyrolysis led to 7. Ring contraction of 9 by S-analogous Wittig ether rearrangement led to 20 which was converted to the diene 5 via oxidation to the disulfoxide 21 and pyrolytic elimination of methane sulfenic acid. Attempts to prepare 6 and 8 via similar routes from 11 failed. Electron absorption spectra and fluorescence spectra of 5 and 7 are discussed in terms of n-π interaction in 5 and π-π interaction in 7.
Molecular Determinants for Drug-Receptor Interactions. 6. Proton 500 MHz NMR Spectra of the Narcotic Antagonists Naloxone and Naltrexone by Two-Dimensional 1H–1H Chemical Shift Correlation Spectroscopy
Authors: Perly Bruno , Pappalardo Giuseppe C. , Grassi Antonio
Published: March 2015

The full analysis of the 1H NMR spectra of naloxone and naltrexone (hydrochloride salts, in 2H2O solution) was performed by using an high-frequency (500 MHz) spectrometer and the recent technique of two-dimensional (2D ) homonuclear shift spectroscopy. The 1H-1H connectivities allowed detection of correlated resonances and assignments of multiplets. The shapes of the contour levels of the COSY 45 spectra were also used to check the relative signs of coupling constants. The refinement of spectral parameters of some component spin-systems of the complex spectra was performed by computerized iterative simulation of patterns.

The spectral analysis provided proton coupling constants that allowed to establish a slightly distorted-chair conformation of the piperidine ring in both compounds.

The magnetic non-equivalence found for the protons bonded to C-17 atom (part of the N-alkyl fragment) was found to be larger in naltrexone than in the analogous naloxone. This fact, while no significant differences were observable in the chemical shifts of corresponding protons of the rigid molecular backbone of the two narcotic antagonists under study, was assigned to smaller degree of internal conformational flexibility of the N-methylcyclopropyl group in naltrexone with respect to that of the N-methylallyl group in naloxone.

The above findings appeared in good agreement with our previously proposed views based on results from 13C relaxation times studies, which suggested the possible correlation of the motional rates of the N-methyl-R group to the pharmacological activity of antagonist compounds. This would consist in a direct correlation between decreasing flexibility of the N-bonded fragment and increasing antagonistic potency.
Synthesis of Pyranobenzopyranopyridines and Benzodipyran Derivatives
Authors: Hishmat O. H. , Khalil Kh. M. A. , El-Naem Sh. I. , el-Rahman A. H. Abd
Published: March 2015

6-Formyl-7-hydroxy-5-methoxy-2-methylchromone on bromination yields the 8-bromo derivative or the 8-bromo-6-formyl-5,7-dihydroxy derivative depending on the reaction condition. Cyclization of both leads to the corresponding 3-acetyl-, 3-benzoyl-, 3-carboxamido-, 3-carbethoxybenzodipyran derivatives.

The 3-acetylbenzodipyran derivative when treated with ethyl acetoacetate or ethyl cyanoacetate in the presence of ammonium acetate yields the corresponding dihydropyranobenzopyranopyridine dione or the dihydropyranobenzopyranopyridine trione.

The reaction of the 3-acetyl derivative with cyanoacetamide in the presence of ammonium acetate affords the substituted pyranobenzopyranopyridine dione.

The 3-acetyl derivative undergoes self condensation to form the substituted benzopyranobenzopyran derivative.
Synthesen neuer Fe–P-Käfigverbindungen / Syntheses of New Fe–P Cage Compounds
Authors: De Rajib Lai , Vahrenkamp Heinrich
Published: March 2015

Four reaction types were used with the aim of obtaining new cage compounds of composition Fex(CO)y(PR)z- with R = Me, Ph, Tol: oxidation of the compounds Fe2(CO)6(PHR)2, photolysis thereof, reaction between RPCF and Fe2(CO)8
2- . and reaction between P-Cl containing iron complexes and Fe(CO)4
2_. Besides several known products, e.g. Fe3(CO)9(PR)2 or Fe4(CO)11(PR)2, and derivatives of the Fe2(CO)6(PRX)2 butterfly type complexes, the new octabisvalene shaped compounds Fe4(CO)2(PR)4 with R = Me, Ph, Tol were obtained and confirmed by a crystal structure analysis for R = Me, Side products of the oxidative conversions were Fe4(CO)12(P2Me2)(MeP-C2H4-PMe) and Fe4(CO)12(P2Tol2)(PHTol)2 which can be derived from the octabisvalene type. Side products of the irradiative conversions were Fe3(CO)8(PPh)(PHPh)2 and (CO)3Fe(μ-PHPh)2Fe(CO)(C6H8). the structure of the latter being proved crystallographically.