bluuebunny/crossref_metadata_2025 huggingface dataset:
From task-based training to task-based instruction: Novice language teachers’ experiences and perspectives
Authors: Bryfonski Lara
Published: June 2021

This study investigated the relationship between task-based teacher training and novice English language teachers’ cognitions and implementations of tasks in Honduran bilingual schools. After participating in a four-week training program on task-based language teaching, teachers with little or no prior teaching experience designed task-based lessons and were video-recorded implementing those lessons with English language learners ages 5 to 12. Following the classroom observation, teachers participated in a stimulated recall interview. A rubric aligned with 10 key principles of task-based language teaching (TBLT) as outlined by Long (2015) was used to rate teachers’ performance and code stimulated recalls. Ratings of video observations showed varied success in TBLT implementation after training, with some teachers’ lessons clearly aligned with key TBLT principles, and others relying on focus on forms strategies. Analysed data also uncovered a link between previous training and teaching experiences and the success of teachers’ implementations. Stimulated recalls showed that teachers focused primarily on maintaining a cooperative learning environment, and less on reactive aspects of TBLT such as providing corrective feedback. Results are discussed in terms of their implications for teachers and teacher training programs seeking to implement TBLT as an approach to language teaching.
Digitizing the story-writing process for EFL primary learners: An exploratory study
Authors: Cheung Anisa
Published: June 2021

The benefits of using digital storytelling are well documented in the literature. Whether and how these advantages can be extended to digital story-writing, especially for young learners, remains underexplored. Recent advancement in technology has the potential of streamlining the stages of planning and revising in a process approach to second language writing. The present study examined how English teachers in two Hong Kong primary schools adopted a process approach to teach digital story-writing. They planned eight writing lessons for 10 Primary 3–4 classes. Students were taught to use Google Slides to write their stories on iPads and complete a recording in small groups, which were then published on an online platform. Findings from focus-group interviews, lesson observations and student writings revealed that students were highly engaged in the lessons, and their writings also had fewer grammatical mistakes. However, they rarely engaged in meaningful dialogues during group work, whilst some teachers also expressed concerns about time constraints and their own readiness to use digital story-writing, which may hinder successful implementation of this innovative approach in classroom settings. Implications of how digital story-writing can be effectively deployed on young learners are discussed.
Structural form and experimental research of truss arch bridge with multi-point elastic constraints
Authors: Qiu Chen , Xie Xiaoli , Pang Mulin , Song Huilan
Published: June 2021

With the increase of the arch bridge span, the mechanical properties of arch bridges will decrease rapidly. In order to solve this problem, triangular net is set between the arch rib and girder to form a kind of truss arch bridge in which arch rib acts as top chord, girder acts as lower chord, triangular net acts as web member, and hangers provide elastic restrains at several points. The triangle stability of the truss can improve linear stiffness of arch rib and girder, which will thus improve the mechanical properties of arch bridges. A test bridge with a span of 50 m was built to prove the superiority of the truss arch bridge with multi-point elastic constraints (MTAB). Structural stresses and displacements were obtained through dead load experiments, and the mechanical properties of the structure were calculated through the finite element (FE) software. It is turned out that, compared with the conventional through arch bridge (CTAB), the mechanical performance of the MTAB is greatly improved. The test values of structural stresses and displacements match calculation values well. Moreover, with the same steel consumption, the more layers of the triangular net, the better the mechanical properties of the structure.
The Danish Health and Wellbeing Survey: Study design, response proportion and respondent characteristics
Authors: Rosendahl Jensen Heidi Amalie , Thygesen Lau Caspar , Møller Sanne Pagh , Dahl Nielsen Maj Britt , Ersbøll Annette Kjær , Ekholm Ola
Published: June 2021

Aims:

This study aimed to describe the study design and respondent characteristics (including non-response analyses) of the Danish Health and Wellbeing Surveys in 2015 and 2019 and a follow-up survey that was carried out during the COVID-19 pandemic in 2020.

Methods:

The Danish Health and Wellbeing Survey is the Danish part of the European Health Interview Survey (EHIS). The samples in 2015 ( N=12,000) and 2019 ( N=14,000) were both based on a simple random selection of individuals aged ⩾15 years from the Danish Civil Registration System. All individuals from the sample in 2019 who were still alive and living in Denmark were reinvited for a follow-up survey in 2020 ( N=13,474). Data in all surveys were collected via self-administered questionnaires (web or paper based). The questionnaires in 2015 and 2019 included the EHIS model questionnaire as well as national questions, whereas the questionnaire in 2020 mainly focused on physical and mental health, employment and working lives, and health behaviour.

Results:

The overall response proportion declined slightly between 2015 (48.4%) and 2019 (47.4%) but went up to 49.8% in the follow-up survey in 2020. Unit non-response was associated with, for example, male sex, younger age, being unmarried and lower educational level but not with degree of urbanisation. In all, 5000 individuals completed the questionnaire in both 2019 and 2020.

Conclusions:

The results are in line with most previous research on non-response in health surveys. However, an association between degree of urbanisation and non-response has been suggested in previous studies. This association was not found in our study.
Barriers to domestic retrofit quality: Are failures in retrofit standards a failure of retrofit standards?
Authors: Fylan Fiona , Glew David
Published: June 2021

Thermal retrofits of homes are central to the UK's fuel poverty and net zero carbon policies but there are concerns about poor quality installation and so new standards are to be introduced (PAS2035). We have explored retrofit installers' perceptions of the barriers to installing internal wall insulation (IWI) and of current regulations and standards for retrofits. We conducted four focus groups with retrofit installers. Thematic analysis identified three themes. (1) IWI is viewed as impractical in situations other than new builds, extensions and conversions as it is too time-consuming and expensive. (2) Installing IWI is perceived as an unskilled job with no need for training or referring to standards during installation. (3) Because standards lack credibility, installers can be sceptical of potential problems caused by on-site installation adaptations, for example thermal bridging. Our results show that retrofit standards have not improved retrofit quality. Awareness and credibility of standards is low, and new standards (PAS2035) will introduce additional costs which may reduce the pool of installers willing to engage in the retrofit market. Policies need to address installer training, professional identity and social practices, and reduce barriers to change in order to increase success.
Let’s talk about sex: Discourses on sexual relations, sugar dating and “prostitution-like” behaviour in drug treatment for young people
Authors: Andersen Ditte , Thing Ida Friis
Published: June 2021

Background:

Sexual relations are a recurrent theme in drug treatment that aims for a holistic inclusion of concerns considered important in young people's lives. Nevertheless, it remains understudied how counselors attend to this theme

Aim:

To investigate the discourses on sexual relations in drug treatment for young people provided by the Scandinavian welfare state of Denmark

Analysis:

Drawing on qualitative interviews with 16 counselors the analysis first identifies three discourses that legitimize sexual relations as a theme in drug treatment by linking the theme to a) pleasure, b) risks, and c) problems. These discourses legitimize the theme by constructing sexual relations as part of the good life, as potentially harmful, or as related to past trauma triggering present problems. Second, the analysis identifies a gendered storyline on sexual relations in exchange economies, e.g., sugar dating, described by some counselors as “prostitution-like” behavior.

Findings:

The gendered storyline is almost exclusively linked to young women's behavior and produces a gendered shame by indicating deviant femininity. Simultaneously, the storyline taboos how the young men may experience vulnerable sexual relations in exchange economies

Conclusion:

Alternative discourses can provide a broader repertoire of subject positions to the benefit of all genders.
Pediatric evidence-based imaging guidelines for adult trauma providers significantly reduces radiation exposure to children
Authors: Wu Anna , Edwards Mary J , Le Rachel , Ata Ashar , Adderly Jasmine , Savage Colleen , Rosati Carl , Edwards Kurt , Duncan Luke
Published: June 2021

Introduction

Evidence suggests that stand-alone pediatric trauma centers outperform adult and combined adult/pediatric trauma centers in limiting radiation exposure to injured children. We sought to determine the impact of implementing evidence-based guidelines for pediatric imaging at a combined adult (level 1) and pediatric (level 2) center. The initiative focused on trauma/critical care surgeons as the pediatric surgeons did not participate in the resuscitation and initial evaluation of injured children.

Methods

Imaging guidelines were developed from existing clinical studies. After 3 months of education, guidelines were implemented, and regular feedback was given to providers regarding compliance. Data were collected from the trauma registry for all pediatric patients (aged less than 15 years), in calendar years 2017 (pre-guideline) and 2019 (post-guideline). All admissions were analyzed, with subgroup analysis of children with multisystem trauma admitted to the trauma surgery service.

Results

Following guideline implementation, mean computed tomography (CT) scans per injured child fell by over 50% (.93 vs .45). For patients admitted to the trauma service, the mean fell by 58% (1.82 vs 0.76). The number of patients receiving more than 1 CT significantly decreased for all children (26% vs 10%), and particularly those admitted to the trauma service (52% vs 17%). During this time, there was only one injury missed at the initial admission, which was clinically insignificant (non-displaced skull fracture).

Conclusions

Implementation of evidence-based guidelines for imaging eliminates disparity in practices between a combined adult/pediatric trauma center and stand-alone pediatric trauma centers.
Composite synchronization on two pairs of vibrators in a far super-resonant vibrating system with the single rigid frame
Authors: Zhang Xueliang , Hu Wenchao , Gao Zhiguo , Liu Yunshan , Wen Bang-Chun
Published: June 2021

In the present work, a new dynamical model with a single rigid frame driven by two pairs of vibrators, of which each pair of vibrators is engaged with each other by gear mechanism, is proposed to explore the composite synchronization of the system. The motion differential equations and vibration responses of the system are given first. The theory condition for achieving composite synchronization of the system is obtained, by using the average method to deduce the average torque balance equations of the two pairs of vibrators. According to the Hamilton’s theory, the system stability condition is presented, and it is mainly determined by the structural parameters of the system. The synchronous stable regions and stability ability versus the key parameters of the system are qualitatively discussed in numeric, and further quantitatively verified by simulations. It is shown that, in engineering, the reasonable working points of the system, should be selected in the region where the stable phase difference of the two pairs of vibrators is stabilized in the vicinity of zero. Only in this way, can the exciting forces of the two pairs of vibrators be positively superposed, and the linear motion of the system in the vertical direction be realized.
Predicting m-shopping in the two largest m-commerce markets: The United States and China
Authors: Ertz Myriam , Jo Myung-Soo , Kong Ying , Sarigöllü Emine
Published: June 2021

This research examines the factors affecting consumers’ mobile shopping (m-shopping) intentions in China and the United States. Drawing on the hedonic-motivation system adoption model (HMSAM), it is proposed that perceived ease of use affects m-shopping intentions; furthermore, this relationship is mediated by perceived usefulness, perceived enjoyment, and control. A survey-based cross-sectional analysis involving a total of 720 respondents constitutes the methodology of this study. In the United States, 409 responses from American citizens or residents were obtained from surveys administered online by MTurk. In China, 311 responses from Chinese consumers were obtained from surveys administered online by Sojump. Perceived usefulness, an extrinsic motive, directly affects behavioral intentions, especially for Chinese consumers, and this effect is also much stronger and complemented by an indirect effect for the Chinese (relative to American) consumers. In contrast, intrinsic motives of joy and control, which are strongly affected by perceived ease of use, do not influence intentions in either market. However, joy exerts an indirect influence on m-shopping intentions, but only for Chinese consumers. These results pertain to the specific context of m-shopping and establish further the importance of distinguishing between utilitarian and hedonic factors, especially across different markets.
Mental health in subsidized housing: Readiness to assist residents with mental health issues in subsidized housing from the perspectives of housing employees
Authors: Jung Hyejin , Jaime Jose , Lee Sharon
Published: June 2021

People in subsidized housing are likely to suffer from mental health issues. However, little is known about subsidized housing employees’ readiness to address the residents’ mental health needs. This qualitative study explores the perspectives of housing employees on their readiness to assist subsidized housing residents’ mental health needs. A total of 32 subsidized housing employees participated in five focus groups. Thematic analysis revealed four key themes: prevalence of mental health issues, unexpected role as housing employees, multi-level barriers in assisting residents with mental health needs, and the need for mental health support in subsidized housing. Findings highlight the need for integrated care, including social work services in subsidized housing. Social workers may have various potential roles to serve the mental health needs of subsidized housing residents. Also identified was the need for mental health education and training among subsidized housing employees.
Throughput optimization of multi-hop and multi-path cooperation in WPSNs with hardware noises
Authors: Yuan Lina , Chen Huajun , Gong Jing
Published: June 2021

This paper proposes a novel multi-path and multi-hop wireless powered sensor network in case of hardware impairment, constituting an energy node, one source node, single sink node, and a series of distributed relay sensor nodes, where the energy node transmits wireless energy to all terminals in the first stage, and the relay sensor nodes relay the information of the source node to the sink node in the second stage. There exists M available paths between the source node and sink node, one of which is chosen for serving source-sink communication. To enhance the minimum achievable data rate, we propose a multi-hop communication protocol based on time-division-multiple-access and an optimal throughput path algorithm. We formulate the time allocation optimization problem about energy and information transmission of the proposed multi-hop cooperation, and confirm through abundant simulation experiments that the proposed scheme can availably improve user unfairness and spectral efficiency, and thus enhance its throughput performance.
The Impact of Maternal Work Status on the Nutrition and Health Status of Children
Authors: Abbi Rita , Christian Parul , Gujral Sunder , Gopaldas Tara
Published: June 2021

The effect of mothers’ work status on their children's nutrition and health was determined from data from 1,990 rural children, one to six years of age, from Chandrapur District, Maharashtra, India. The relative risk of a child of a working versus a non-working mother being malnourished was 1.7 by weighs for age and 1.8 by height for age. The relative risks of developing anaemia and vitamin-A deficiency were 1.4 and 1.5 respectively for the children of working mothers. The relative risks for younger children of getting measles, severe diarrhoea, and worm infestation were significantly higher in those whose mothers worked. Family income and child's age were significant intervening factors in the ad verse effects of maternal work status on all nutrition- and health-status variables except pneumonia and vitamin-A deficiency. Poor income appeared to be the major detrimental factor, with the mother's working status being an aggravator.
Traditional Food-Processing Technology and High-Protein Food Production
Authors: Mensah E. O. , Sefa-Dedeh S.
Published: June 2021

Studies were undertaken on a high-protein gari-like dry product, developed previously, prepared from corn (Zea mays) and cowpea (Vigna unguiculata) flours and dried by the technique traditionally used for roasting gari, a commonly eaten food made from cassava. The product's water absorption and swelling characteristics were lower than those of gari; but its particle size, crispness, colour, and flavour were rated acceptable when compared to gari.
Values and control in type 1 diabetes beyond glycemic outcomes: A qualitative interview study of everyday life with an insulin pump
Authors: Cleal Bryan , Nexø Mette Andersen , Schmidt Signe , Rytter Karen , Nørgaard Kirsten , Willaing Ingrid
Published: June 2021

Objectives

Diabetes technology provides people with diabetes with new opportunities, but the transformations allowed by new technology do not necessarily provide improvements in clinical metrics applied in diabetes care. This study seeks to understand how everyday life impacts on the way people use diabetes technology and how this influences diabetes care.

Methods

Individual semi-structured qualitative interviews with 21 adults with type 1 diabetes treated with insulin pumps were recruited from two Danish diabetes outpatient clinics. Data were analyzed abductively and interpreted according to predetermined and emergent perspectives.

Results

Transformations in care practices derived from new technological therapies were generally well-supported by healthcare providers, but adaptation to everyday life was often challenging. More advanced technology enabled people to better control diabetes, but the control they sought was defined by individual life experiences/factors. Work involved in controlling blood glucose could cause a sense of feeling controlled by diabetes in everyday life.

Discussion

Everyday life with diabetes is often characterized by uncertainty and individual coping strategies are imbued with values that extend beyond purely clinical concerns and reflect the sociality of everyday life. The social values influencing individual decision-making regarding diabetes technology could be effectively expanded and enhanced with integrated peer-supported learning.
Light-induced [2 + 2] Cycloaddition of 6-Methoxy-2-naphthonitrile to 2-Chloroacrylonitrile
Authors: Al-Jalal Nader A. , Pritchard Robin G. , McAuliffe Charles A.
Published: June 2021

6-Methoxy-2-naphthonitrile undergoes photocycloaddition to 2-chloroacrylonitrile to give [2 + 2] cyclobutane adducts (1a and 1b), the structure of one of which (1a) has been unambiguously confirmed by an X-ray structural analysis.
Kinetics and Mechanism of Ruthenium(III) Chloride Catalyzed Oxidation of Propane-1,3-diol by Thallium(III) in Acid Perchlorate Medium
Authors: Bhasin Menka , Sharma Indu , Sharma P. D.
Published: June 2021

The mode of electron transfer in ruthenium(III) chloride catalyzed oxidation of propane-1,3-diol by thallium(III) is explained by hydride ion abstraction.
Utility of [(p-Sulfonamidophenyl)azo]malononitrile in the Synthesis of Polyfunctionally Substituted Pyrimidine, Pyrazole, Isoxazole and Pyridazine Derivatives
Authors: Hassanien Abu Zeid Abd El-Baset , Hafiz Ibrahim Saad Abdel , Elnagdi Mohamed Hilmy
Published: June 2021

[( p-Sulfonamidophenyl)azo]malononitrile and/or [( p-sulfonamidophenyl)azo]acrylonitrile derivatives react with various reagents to afford pyrimidine, pyrazole, isooxazole and pyridazine derivatives with interesting biological activities via initial addition to either the cyano or amino group followed by cyclization.
Alkylation of 1-(3,4-Disubstituted Phenyl)-2-thioxo-1,2,5,6-tetrahydropyrimidin-4(3H)-ones
Authors: Kantminiene Kristina , Beresnevičius Zigmuntas , Mikulskiene Gema , Kihlberg Jan , Broddefalk Johan
Published: June 2021

The results of a comprehensive investigation of the alkylation of the title compounds with Mel in butanone in the presence of K2CO3 are presented.
A 13C NMR Method for Determining the Stereochemistry of the A/B Ring Junction in B-Norsteroids
Authors: Hanson James R. , Hitchcock Peter B. , Thangavelu Vasuki , Uyanik Cavit
Published: June 2021

A correlation between the position of the 13C NMR signal for the C-10 methyl group (C-19) and the stereochemistry of the A/B ring junction has been established and applied to the determination of the stereochemistry of the products of the hydroboration of B-norandrosta-3,5-dien-17-one.
New Desulfurdimerization of Dithioketals Induced by a 2,2′-Bipyridine Ligated Nickel(0) Complex
Authors: Lourak Moushine , Becker Sandrine , Fort Yves , Caubère Paul
Published: June 2021

Desulfurdimerization of various aromatic dithioketals is efficiently induced by a 2,2′-bipyridine ligated nickel(0) complex under mild conditions.
The Crystal Structure of N-(5-Phenyl-1,3,4-oxadiazol-2-yl)-N′ -benzoyl Urea, a Novel Insect-growth Regulator
Authors: Zhong Li , Zhixiang Zhu , Gonghua Song , Xuhong Qian , Jie Sun
Published: June 2021

The crystal structure of N-(5-phenyl-1,3,4-oxadiazol-2-yl)- N′-benzoyl urea, C16H12N4O3, a novel insect-growth-regulator (IGR), has been established; the crystal structure belongs to the triclinic system with Z = 2, and the urea linkage is coplanar with intramolecular hydrogen bond formation, making the structure analogous to a four-ring compound.
Synthesis of Triethyl N-Formyl-N-phosphonomethylglycinate and Diethyl N-Formyl-N-phosphonomethylglycine and Studies of Their Rotational Conformers by Dynamic NMR
Authors: Ziora Zyta , Cierpicki Tomasz , Grembecka Jolanta , Kafarski Paweł
Published: June 2021

Reaction of ethyl N-phosphonomethylglycinate with triethyl orthoformate gave a mixture of triethyl N-formyl- N-phosphonomthylglycinate (3) and diethyl N-formyl- N-phosphonomethylglycine (4), the rotational barriers of which have been investigated theoretically and experimentally.
New Synthetic Approaches to Fused Heterocyclo-quinazolines
Authors: Santagati Andrea , Modica Maria , Scolaro Luigi Monsù , Santagati Maria
Published: June 2021

Fused heterocyclo-quinazolines have been prepared from the versatile and easily obtained intermediate 3-amino-2,3-dihydro-2-thioxo-4(1 H)-quinazolinone 2; their structural elucidation is also reported.
Heterocyclic Synthesis via Enaminonitriles: One-pot Synthesis of Some New Pyrazole, Isoxazole, Pyrimidine, Pyrazolo[1,5-a]pyrimidine, Pyrimido[1,2-a]benzimidazole and Pyrido[1,2-a]benzimidazole Derivatives
Authors: Dawood Kamal M. , Farag Ahmad M. , Kandeel Zaghloul E.
Published: June 2021

A convenient synthesis of some new pyrazole, isoxazole, pyrimidine, pyrazolo[1,5- a]pyrimidine, pyrimido[1,2- a]-benzimidazole and pyrido[1,2- a]benzimidazole derivatives is reported.
Stability of Metal Complexes with a Ligand of Biological Interest: Noradrenaline
Authors: Gérard Christian , Chehhal Hanane , Aplincourt Michel
Published: June 2021

Stoichiometry, equilibrium constants and spectra of iron(III) complexes with noradrenaline have been determined from spectrophotometric measurements; in addition equilibrium constants of complexes with MgII, CdII and PbII have been determined from potentiometric measurements.
A Key Intermediate towards Oxylipins. A Formal Synthesis of (12S)-HETE and (12S)-LTB4
Authors: Benkouider Abdelhamid , Pale Patrick
Published: June 2021

A key intermediate in the synthesis of various oxylipins, the optically active (3 S,5 Z)-3-methoxymethoxyundec-5-en-1-yne, has been obtained in 11 steps starting from propane-1,3-diol, with an overall yield of 14%.
Synthesis of [Tetrakis(1,3-dithiol-2-thiono)-porphyrazinato]magnesiumt
Authors: Polat Merve , Gül Ahmet
Published: June 2021

[Tetrakis(1,3-dithiol-2-thiono)porphyrazinato]magnesium has been prepared by cyclotetramerization of 4,5-dicyano-1,3-dithiol-2-thione.
7-Dehydrosarcophytin, another Novel Diterpenoid from the Soft Coral Sarcophyton elegans of the Indian Ocean
Authors: Anjaneyulu Ammanamanchi S. R. , Gowri Ponnapalli M. , Murthy Moturu V. R. Krishna
Published: June 2021

7-Dehydrosarcophytin (3), another novel diterpenoid, has been isolated from the Indian Ocean soft coral Sarcophyton elegans, in addition to sarcophytin, and its structure elucidated using spectral data.
Configurational Properties of Cyclonona-1,2,4,5,7,8-hexaene and Cyclododeca-1,2,5,6,9,10-hexaene
Authors: Yavari Issa , Norouzi-Arasi Hassan , Nori-Shargh Davood , Fallah-Bagher-Shaidaei Hossain
Published: June 2021

AM1 semi-empirical SCF MO calculations for the structure optimization and configurational properties of cyclonona-1,2,4,5,7,8-hexaene 3, its hexamethyl derivative 4 and cyclododeca-1,2,5,6,9,10-hexaene 5 show that the combination of three allenic units of the same chirality yields an enantiomeric pair which is the most stable configuration of 3, 4 and 5.
Synthesis and Structure of 2-(Triphenylphosphoranylideneamino)tropone and its Utility in the Preparation of New Cyclohepta-annulated Heterocycles1
Authors: Yamamoto Hiroyuki , Ohnuma Manami , Nitta Makoto
Published: June 2021

2-(Triphenylphosphoranylideneamino)tropone is synthesized for the first time and treated with heterocumulenes to give novel cyclohepta-annulated heterocycles in good yields.
NMR, X-Ray and MS Investigations of Ethyl 2-Aroyl-and Ethyl 2-Arylcarbamoyl-4,5- dimethyl-1,2,3,6-tetrahydropyridazine-1- carboxylates: Flexible Multidentate Ligands
Authors: Kolehmainen Erkki , Laihia Katri , Nissinen Maija , Pihlaja Kalevi , Perjéssy Alexander , Loos Dušan , Rudorf Wolf-Dieter , Meyer Peter
Published: June 2021

The 1H and 13C NMR spectral assignments of ethyl 2-aroyl-4,5-dimethyl-1,2,3,6-tetrahydropyridazine-1-carboxylates (1a-1h) and ethyl 2-arylcarbamoyl-4,5-dimethyl-1,2,3,6-tetrahydropyridazine-1-carboxylates (2a-2k) are given based on DQF COSY, 1H,13C HMQC and 1H,13C HMBC-measurements; the dynamics of the tetrahydropyridazine ring has been studied by 1H, 1H EXSY-technique and the structure of one congener (4′-methylphenyl-derivative, 2a) has been confirmed by X-ray structure analysis.
Structural Investigations of C-Nitrosobenzenes. Part 3.1 Solid-state and Solution 13C NMR Studies, and Crystal Structure of E-(4-CIC6H4NO)2
Authors: Fletcher Daniel A. , Gowenlock Brian G. , Orrell Keith G. , Apperley David C. , Hursthouse Michael B. , Malik K. M. Abdul
Published: June 2021

Solid-state and solution 13C NMR data for the monomers and dimers of 3- and 4-substituted nitrosobenzenes, and the crystal structure of E-(4-CIC6H4NO)2 are reported.
A Facile Method for Synthesis of Calix [4] crowns Containing Nitrogen and Sulfur Atoms
Authors: Zheng Qi-Yu , Chen Chuan-Feng , Huang Zhi-Tang
Published: June 2021

A synthesis of calix [4] crowns containing nitrogen and sulfur atoms and bischloroacetamides is reported.
The Direct Carbamoylation of Organometallic Reagents with 1,2,3-Benzotriazole -1-carboxamides
Authors: Katritzky Alan R. , Monteux Daphne A. , Tymoshenko Dmytro O. , Belyakov Sergei A.
Published: June 2021

Various (hetero) aromatic amides are synthesized efficiently by the carbamoylation of organometallic reagents.
Studies on Uracils: Synthesis of Tetrazolo[4’,5':1,6]pyrido[2,3-d]pyrimidines by the Action of Cyano Stabilised Carbanions on 6-Azido-5-formyluracils
Authors: Bhuyan Pulak J. , Lekhok Kushal C. , Sandhu Jagir S.
Published: June 2021

6-Azido-5-formyluracils 2 undergo base catalysed condensation with cyanocarbanions to yield tetrazolo[4’,5':1,6]-pyrido[2,3- d]pyrimidines 4 in good yields.
Vinyltriphenylphosphonium Salt-mediated New Synthesis of Functionalized Maleimides
Authors: Yavari Issa , Asghari Sakineh , Esmaili Abbas Ali
Published: June 2021

N-Methyl-2-chloroacetoacetamide undergoes a complex reaction with dialkyl acetylenedicarboxylates and triphenylphosphine to produce dialkyl 2-( N-methyl-2-chloroacetoacetamide-2-yl)-3-(triphenylphosphoranylidene)-butanedioates, which undergo elimination-cyclization reactions to produce N-methyl-4-acetyl-3-(alkoxycarbonyltriphenylphosphoranylidene)-maleimides.
Iridoids from Carbohydrates via Pauson–Khand Cyclopentane Annulation Mediated Strategies: Preliminary Studies
Authors: Marco-Contelles José , Ruiz Juliana
Published: June 2021

The Pauson–Khand reaction on suitable carbohydrate derivatives obtained from L-arabinose gives annulated pyranosides that can be transformed into advanced synthetic intermediates for the synthesis of iridoid aglycones. Preliminary studies towards this end are described.
Preparation and Characterization of Tetraphenylborate Salts of 2-Aminopyrrole and 1-Alkyl-2-aminopyrroles
Authors: De Rosa Michael , Sellitto Ian , Issac Roy P. , Ralph John , Timken Mark D.
Published: June 2021

Tetraphenylborate salts of 2-aminopyrrole and 1-alkyl-2-aminopyrroles are prepared and found to be stable.
Chemoselective Hydrolysis of Esters by Fungal Lipase
Authors: Chowdhury Abhijit Roy , Tripathi Manish K. , Jinwal Umesh K. , Roy Uma , Kumar Versha V. , Bhaduri A. P. , Roy P. K.
Published: June 2021

Lipase, isolated from Aspergillus niger, exhibits chemoselectivity towards hydrolysis of fatty acid esters and does not hydrolyse carbamates; this has been demonstrated with substrates such as 5 ( N-methoxycarbonyl- N-ethoxycarbonylmethylamino)-2-aryl-2,4-dihydro-3 H-1,2,4-triazol-3-ones.
Aluminium Chloride: A Mild and Efficient Catalyst for Selective Deprotection of 1,1-Diacetates
Authors: Mohammadpoor-Baltork Iraj , Aliyan Hamid
Published: June 2021

A mild, efficient and excellent yield method for the selective deprotection of 1,1-diacetates to the corresponding aldehydes in the presence of aluminium chloride (AICI3) is described.
Synthesis and Magnetic Properties of New Tetranuclear Copper(II)–Nickel(II) Complexes of Macrocyclic Oxamides
Authors: Gao En-Qing , Yang Guang-Ming , Liao Dai-Zheng , Jiang Zong-Hui , Yan Shi-Ping , Wang Geng-Lin
Published: June 2021

Four new oxamido-bridged [Cu3IINiII] complexes of [14]N4 and [15]N4 macrocyclic oxamides have been prepared and characterized, and the magnetic interaction between the Cu(II) and Ni(II) ions has been investigated.
Use of Benzotrifluoride as Solvent for Chromium-catalysed Oxidations with Sodium Percarbonate1
Authors: Delaval Nicolas , Bouquillon Sandrine , Hénin Françoise , Muzart Jacques
Published: June 2021

Chromium(VI)-catalysed oxidations of alcohols and benzylic methylene groups by sodium percarbonate have been carried out in refluxing benzotrifluoride; comparisons with previous studies showed that this solvent is a valuable alternative to 1,2-dichloroethane for such reactions.
Revisiting the Reactions of Phenyl(trihalomethyl)mercury with Tetraphenylcyclone (TPCP)
Authors: Wang Hongxing , Gu Wenxiang , Zhang Gaoju , Huan Zhenwei , Cheng Jin-Pei
Published: June 2021

Unexpectedly high yields of deoxygenation products from the title reactions are observed and rationalized.
Synthesis of Indole Alkaloids and Alkaloidal Precursors: An Improved Synthesis of Flavopereirine
Authors: Manna Ranjan K. , Jaisankar P. , Giri Venkatachalam S.
Published: June 2021

Synthesis of flavopereirine 1, formal synthesis of isogeissoschizines 8 and dihydrocorynantheols 9 through the intermediacy of 3-(2-hydroxyethyl)-6,7-dihydroindolo[2,3-a]quinolizine 3 and also the unexpected formation of the β-carbolines 12 and 13 on Huang-Minion reaction of 2 are described.
Solid State Spectroscopic Studies of Molybdenum Oxo Species with Coordinated ONR Groups
Authors: Cameron Mailer , Gowenlock Brian G. , Vasapollo Giuseppe , Mele Giuseppe , Orrell Keith G. , Apperley David C. , Carley Albert F.
Published: June 2021

A re-investigation of some complexes of molybdenum claimed to contain coordinated C-nitroso compounds has demonstrated that these solids are complex and that π-coordination of RNO cannot be the sole structural component.
Selective Esterification of Nonconjugated Carboxylic Acids in the Presence of Conjugated or Aromatic Carboxylic Acids under Mild Conditions
Authors: Anand Ramesh C. , Vimal  , Milhotra Archana
Published: June 2021

Nonconjugated carboxylic acids are selectively esterified in good yields in the presence of conjugated or aromatic carboxylic acids by stirring over Amberlyst-15 in alcohol at room temperature.
Synthesis and Crystal Structure of a Novel Octahedral Fe4Cr2 Transition Metal Cluster Complex Cp2Cr2Fe4(CO)12(μ6-O)
Authors: Song Li-Cheng , Gao Wen-Qi , Huang Xiao-Ying
Published: June 2021

Reaction of Cp(OC)2Cr=S = Cr(CO)2Cp with Fe3(CO)12 affords an encapsulated μ6-O octahedral Fe4Cr2 cluster complex Cp2Cr2Fe4(CO)12(μ6-O), whose crystal structure is determined by X-ray diffraction analysis.
First Synthesis of 1,1,4,4-Tetrakis(2-hydroxyphenyl)-butane Type Compounds from Condensation of p-Substituted Phenol Derivatives with 2,5-Dimethoxytetrahydrofuran in Trifluoroacetic Acid
Authors: Banihashemi Ahmad , Rahmatpour Ali
Published: June 2021

Condensation reactions of 2,5-dimethoxytetrahydrofuran with p-substituted phenols and 2-naphthol in trifluoroacetic acid produce 1,1,4,4-tetrakis(2-hydroxyphenyl)butane type compounds and 1,2-bis(1,3-dibenzo[ a,j]xanthyl)ethane in good yields.
Preparation of 4,13,19,28-Tetrahydroxy-9,9,24,24-tetramethyl[2.1.2.1]metacyclophane, a Novel exo-Hydroxycalixarene Analogue
Authors: Miyazawa Akira , Suzuki Yasuzo , Sawada Tsuyoshi , Mataka Shuntaro , Tashiro Masashi
Published: June 2021

A novel 4,13,19,28-tetrahydroxy-9,9,24,24-tetramethyl[2.1.2.1]metacyclophane is prepared from bisphenol A in six steps and found to have a saddle structure in solid state.
Copper(I) Chloride/Kieselguhr: A Versatile Catalyst for Oxidation of Alkyl Halides and Alkyl Tosylates to the Carbonyl Compounds
Authors: Hashemi Mohammed M. , Beni Yousef Ahmadi
Published: June 2021

Copper(I) Chloride adsorbed on Kieselguhr in the presence of oxygen catalyses oxidation of alkyl halides and alkyl tosylates to the aldehydes and ketones in high yields.
Lanthanide Bis(trifluoromethylsulfonyl)amides as Effective Reusable Catalysts for Catalytic Friedel–Crafts Acylation
Authors: Nie Jin , Xu Jun , Zhou Guangyong
Published: June 2021

By using a catalytic amount of a lanthanide bis(trifluoromethylsulfonyl)amide, Ln(NFf2)3, the Friedel–Crafts acylation of substituted benzene proceeds smoothly under mild conditions and the catalysts are easily recovered from the reaction mixture.
Zinc-mediated Reductive Dimerization Cyclization of Ethyl Arylmethylidenecyanoacetates in Aqueous Media
Authors: Wang Lei , Zhang Yongmin
Published: June 2021

Zinc-mediated reductive dimerization–cyclization of ethyl arylmethylidenecyanoacetates occurs to give diethyl 2-amino-3-cyano-4,5-diaryl-1,3-cyclopentenedicarboxylates in moderate to good yields the trans, trans-form isomer being the major product.
Effect of Dimethylformamide on the Ring Opening Insertion Polymerization of ε-Caprolactone
Authors: Kavros Alexander , Robinson Yashica L. , Rimmer Stephen
Published: June 2021

Ring-opening insertion polymerization of ε-caprolactone is retarded in dimethylformamide when catalysts such as dibutyl tin oxide, zinc acetate and titanium tetrabutoxide are employed.
Synthesis of the Pseudoguaianolide and Guaianolide Skeleton by Cleavage of the Ether Bridge of 8-Oxabicyclo[3.2.1]octan-3-one Derivatives
Authors: Rubinger Mayura M. M. , Mann John
Published: June 2021

The synthesis of three new polysubstituted cycloheptenones by cleavage of the ether bridge of 8-oxabicyclo[3.2.1]octan-3-one derivatives is described, together with the application of this methodology in the construction of the guaianolide and pseudoguaianolide skeleton.
Thermodynamic Study of the NaCI + CaCI2 + H2O Mixed System by EMF Measurements at Different Temperatures
Authors: Galleguillos H. R. , Hernandez-Luis F. , Fernández-Mérida L. , Esteso Miguel A.
Published: June 2021

Activity coefficients for NaCI in the NaCI + CaCI2 + H2O ternary system are determined from emf measurements of galvanic cells at 15, 25, 35 and 45 °C. The experimental data were analysed using the Harned, Scatchard and Pitzer treatments.
Non-bonded S · · · N Interactions in Organosulfur Derivatives: Crystal and Molecular Structures of [2-(4,4-Dimethyl-2-oxazolinyl)phenyl] Benzyl Sulfide and Bis[2-(4,4-dimethyl-2-oxazolinyl)phenyl] Sulfide
Authors: Mugesh G. , Singh Harkesh B. , Butcher Ray J.
Published: June 2021

The synthesis and structural characterisation of two low-valent sulfur derivatives stabilised by S · · · N intramolecular non-bonded interactions are described.
Correlation Analysis of Reactivity in the Oxidation of Substituted Benzyl Alcohols by Benzyltrimethylammonium Tribromide
Authors: Kothari Anjana Seema , Banerji Kalyan K.
Published: June 2021

The oxidation of benzyl alcohol by benzyltrimethylammonium tribromide involves an almost synchronous cleavage of the α-C–H and O–H bond.
Photoinduced Electron Transfer Reactions of Anthracene in CF3SO3H–CF3CO2H
Authors: Pagni Richard M. , Mamantov Gleb , Hondrogiannis George , Unni Aditya
Published: June 2021

Photolysis of anthracene in a mixture consisting of 2% CF3SO3H in CF3CO2H (w/w), where anthracene is partially protonated, gives a mixture of oxidized, neutral and reduced monomeric and dimeric products, initiation of this chemistry being photoinduced electron transfer from anthracene to protonated anthracene.
Synthetic Studies of Dihydroagarofuran Sesquiterpene: An Improved NBS–THF–H2O System for Stereoselective Construction of Tetrahydrofuran Moiety
Authors: Sun Liang Dong , Tu Yong Qiang , Xia Wu Jiong
Published: June 2021

An improved aqueous NBS–THF system in a range of media has proved to be effective for stereoselective construction of the bromotetrahydrofuran moiety of dihydroagarofuran sesquiterpene polyesters from the corresponding β-hydroxyalkene.
Application of Commercially Available Anhydrous Potassium Fluoride for a Convenient Synthesis of Ketene Dithioacetals
Authors: Mashraqui Sabir H. , Hariharasubrahmanian Harini
Published: June 2021

Commercially available anhydrous KF without activation or solid support promotes condensation between active methylene compounds, carbon disulfide and an alkylating agent in dry DMF to allow the preparation of a variety of ketene dithioacetals in fair to good yields under ambient conditions.
Synthesis of Highly Unsymmetrical Phthalocyanines
Authors: Ali Hasrat , Sim Siv K. , van Lier Johan E.
Published: June 2021

The synthesis of unsymmetrical sub-phthalocyanines and their ring enlargement to yield the highly unsymmetrical phthalocyanines is reported.
Solvent Extraction Equilibrium in the CuSO4–H2SO4–LIX 984–ESCAID 103 Systern
Authors: Alguacil Francisco Jose , Simpson Jaime , Navarro Patricio
Published: June 2021

A previously determined thermodynamic model for extraction equilibrium is used as a basis to predict experimentally measured distribution coefficients for the CuSO4–H2SO4–LIX 984–Escaid 103 solvent extraction system at 25 °C and aqueous copper concentrations in the range 0.01–2.0 gL−1, the copper loading isotherm is also obtained.
Kinetic Studies on the Formation and Decomposition of Bis(peroxo)oxochromium(VI) in Aqueous Solution
Authors: El-Ayaan Usama , Reisacher Rosmarie , Linert Wolfgang
Published: June 2021

The reaction of chromic acid with hydrogen peroxide is studied kinetically and the stability of the product throughout the formation of adducts with donor molecules is investigated.
Reactions with Hydrazonoyl Halides. Part XXV.1 Synthesis of Some New 2,3-Dihydro-1,3,4-thiadiazoles and 5-Arylazothiazoles
Authors: Abdelhamid Abdou O. , Abdel-Riheem Nadia A. , Emam Hussein A.
Published: June 2021

2,3-Dihydro-1,3,4-thiadiazoles are synthesized by the reaction of hydrazonoyl halides with alkyl benzoylhydrazinecarbodithioates in ethanolic triethylamine whereas α-keto hydrazonoyl halides react with benzoylthiosemicarbazides to afford 5-arylazothiazoles.
The Tetracyanoethylene Catalysed Methanolysis of Androstane 2,3-Epoxides
Authors: Hanson James R. , Kiran Ismail
Published: June 2021

Unlike other acidic systems, the tetracyanoethylene catalysed methanolysis of androstane 2,3-epoxides proceeds normally without giving products arising from the transannular participation of a 5α,6α-epoxide, a 5α-hydroxy group or a 5(6)-ene.
Synthesis of a Heteroannulated Furanose via Intramolecular Michael Addition in an ω-Hydroxy α,β-Unsaturated Nitrile
Authors: Marco José L. , Fernández Susana
Published: June 2021

An highly stereospecific Michael addition in the ω-hydroxy α,β-unsaturated nitrile 4, obtained from ‘diacetone glucose’ 2, leading to annulated furanose 7 is reported.
The Barbier Reaction of 1-(Chloromethyl)benzotriazole with Aldehydes and Ketones mediated by Samarium Diiodide
Authors: Huang Zhi-Zhen , Jin Hong-Wei , Duan De-Hui , Huang Xian
Published: June 2021

1-(Chloromethyl)benzotriazole can smoothly undergo the Sml2–Barbier reaction with aldehydes and ketones to give 1-β-(hydroxyalkyl)benzotriazoles under very mild conditions.
Epoxidation of Alkenes using Equimolar Levels of t-BHP Catalysed by Polybenzimidazole (PBI)-supported Molybdenum(VI)
Authors: Leinonen Salla-M. , Sherrington David C.
Published: June 2021

Epoxidation of cyclohexene, styrene and 4-vinylcyclohexene using equimolar levels of tert-butylhydroperoxide ( t-BHP) as the oxidant and a polybenzimidazole-supported molybdenumn(VI) catalyst (PBI.Mo) can be achieved in moderate to good yields (50–70%) by appropriate choice of conditions.
Preparative-scale HPLC Resolution of Metallacyclic η3-Allyltricarbonyliron Complexes and Determination of the Absolute Configuration by X-Ray Crystal Structure Analysis
Authors: Schobert Rainer , Pfab Hermann , Böhmer Jutta , Hampel Frank , Werner Andreas
Published: June 2021

Racemates of (η3-allyl)tricarbonyliron lactone complex Fe(CO)3{η1:η3-C(O)XCH2CHCMeCH2} 1a (X = O) and (η3-allyl)tricarbonyliron lactam complex 2a (X = NMe) are resolved on a preparative scale by HPLC on cellulose tris(3,5-dimethylphenyl)carbamate/silica gel RP-8 and the absolute configuration of (-)-2a is determined by X-ray crystal structure analysis.
Phosphorylation of Amines by the UV-light Mediated Fragmentation of a 2-Phosphabicyclo[2.2.2]octene 2-Oxide
Authors: Keglevich György , Szelke Helga , Nagy Zoltán , Dobó András , Novák Tibor , Tőke László
Published: June 2021

Irradiation of the title compound 1 at 254 nm in the presence of alkylamines or dialkylamines leads to the formation of phosphinic amides 3 and 4, respectively.
The Oxidation of Some Steroidal Dienes and Trienes with Chromic Acid
Authors: Hanson James R. , Kiran Ismail
Published: June 2021

The chromic acid oxidation of steroidal 2,4- and 3,5-dienes and 2,4,6-trienes is shown to take place at the secondary termini of the alkenes rather than at the allylic positions and is rationalized in terms of a sequence of 1:4-additions of chromic acid.
Deoxygenation Reaction of Phenyl Nitronyl Nitroxides with the Strong Acceptors TCNQF4 and TCNQ
Authors: Nakatsuji Shin'ichi , Takai Atsushi , Ojima Takeo , Anzai Hiroyuki
Published: June 2021

The reaction of certain phenyl nitronyl nitroxide derivatives with strong acceptors such as TCNQF4 or TCNQ in appropriate solvents give the corresponding imine nitroxide derivatives by an anomalous deoxygenation reaction with acceptors in a selective manner.
Heterocycles from 3,4,5,6-Tetrachloro-1,2-benzoquinone
Authors: Aly Ashraf A. , Shakar Rafat M.
Published: June 2021

Reactions of 3,4,5,6-tetrachloro-1,2-benzoquinone with active methylene derivatives, diethyl oxalate and diphenylacetylene, provided various novel heterocyclic derivatives.
The Preparation of Furano-steroid Analogues of Demethoxyviridin
Authors: Boynton Juliette , Hanson James R. , Kiran Ismail
Published: June 2021

The syntheses of a C-4:C-6 furano-steroid by the base-catalysed cyclization of 6α-acetoxyandrost-4-ene-3,17-dione and of a C-4:C-6 tetrahydrofuran by the cyclization of 3β,6β-dihydroxy-4β-hydroxymethylandrostan-17-one, are described.
Anionic Micellar Effects on the Benzophenone-sensitized Photolysis of N-(1-Naphthoyl)-N-phenyl-O-benzoylhydroxylamine
Authors: Kaneko Tsuyoshi , Kubo Kanji , Sakurai Tadamitsu
Published: June 2021

The title hydroxylamine in sodium dodecyl sulfate micelles containing benzophenone is subjected to photorearrangements giving benzoyloxy- and phenyl-migrated products along with fragmentation products; subsequent photohydrolysis of the 1,5-benzoyloxy-rearranged product proceeds selectively.
Reactions of 4-Hydroxycoumarin and 4-Hydroxyfurocoumarins with α,β-Unsaturated Nitriles. Mass Spectrometry of the New γ-Pyrano-α-pyran Derivatives
Authors: Yakout E. M. A. , Ibrahim N. M. , Ghoneim Kh. M. , Mahran M. R. H.
Published: June 2021

Reactions of 4-hydroxycoumarin and 4-hydroxyfurocoumarins with αβ-unsaturated nitriles provide routes to a range of novel pyranocoumarins and furopyranocoumarins, respectively.
A Mixed-metal Mixed-halide Complex Prepared from Zerovalent Copper and Lead Salts: Solution and Solid-state Chemistry
Authors: Kovbasyuk Larisa A. , Vassilyeva Olga Yu. , Kokozay Vladimir N. , Linert Wolfgang , Raithby Paul R.
Published: June 2021

The mixed-metal mixed-halide complex [CuPbBrlL2]2 has been prepared by the direct interaction of zerovalent copper with lead halides and 2-dimethylaminoethanol (HL) in dmso and has been characterized by X-ray crystallography; the structure shows a layer arrangement of the tetranuclear metal units through the μ3-halogen bridging.
Sodium Hypochlorite/Dowex 1X8-200: An Effective Oxidant for the Oxidation of Aromatic Amines to Quinones
Authors: Hashemi Mohammed M. , Beni Yousef A.
Published: June 2021

Polymer supported hypochlorite ion is a useful oxidant for the oxidation of aromatic amines to the corresponding quinones.
Efficient One-pot Thiocyanation of Primary, Secondary and Tertiary Alcohols by in situ Generation of Ph3P(SCN)2. A Modified Procedure
Authors: Iranpoor N. , Firouzabadi H. , Shaterian H. R.
Published: June 2021

The preparation of Ph3P(SCN)2 is modified by using a combination of Ph3P, NH4SCN and Br2 at room temperature for the efficient conversion of primary, secondary and tertiary alcohols to their corresponding thiocyanates in excellent yields.
1,3-Dipolar Cycloaddition of 3-Azido-3-deoxy-1,2:5,6-di-O-isopropylidene-α-D-glucofuranose and C60
Authors: MarcoContelles José , Jagerovic Nadine , Alhambra C.
Published: June 2021

The thermal cycloaddition of azido sugar 3 with C60 gives the chiral azafulleroid 4 in 2.55% yield (8% based in recovered C60).