Novel Synthesis of 4-Fluoropyridines Based on 2-Fluoroallylic Alcohols by Succeeding Ireland—Claisen and Aza-Cope Rearrangements as Key Steps.

Ulrich Wittmann; Frank Tranel; Roland Froehlich; Guenter Haufe

doi:10.1002/chin.200645141

Novel Synthesis of 4-Fluoropyridines Based on 2-Fluoroallylic Alcohols by Succeeding Ireland-Claisen and Aza-Cope Rearrangements as Key Steps

Synthesis ◽

10.1055/s-2006-942411 ◽

2006 ◽

Vol 2006 (13) ◽

pp. 2085-2096 ◽

Cited By ~ 2

Author(s):

Günter Haufe ◽

Ulrich Wittmann ◽

Frank Tranel ◽

Roland Fröhlich

Keyword(s):

Novel Synthesis ◽

Cope Rearrangements ◽

Key Steps

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Total synthesis of (+)-monocerin via tandem dihydroxylation-SN2 cyclization and a copper mediated tandem cyanation–lactonization approach

Organic & Biomolecular Chemistry ◽

10.1039/c4ob00965g ◽

2014 ◽

Vol 12 (31) ◽

pp. 5973-5980 ◽

Cited By ~ 13

Author(s):

U. Nookaraju ◽

Eeshwaraiah Begari ◽

Pradeep Kumar

Keyword(s):

Total Synthesis ◽

Asymmetric Dihydroxylation ◽

Novel Synthesis ◽

Key Steps ◽

Julia Olefination

A simple and novel synthesis of (+)-monocerin was achieved from 3-buten-1-ol employing HKR, Julia olefination, intramolecular tandem Sharpless asymmetric dihydroxylation-SN2 cyclization and a novel copper mediated tandem cyanation–cyclization as the key steps.

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Model Studies To Access the [6,7,5,5]-Core of Ineleganolide Using Tandem Translactonization–Cope or Cyclopropanation–Cope Rearrangements as Key Steps

The Journal of Organic Chemistry ◽

10.1021/acs.joc.7b02030 ◽

2017 ◽

Vol 82 (24) ◽

pp. 13051-13067 ◽

Cited By ~ 6

Author(s):

Jennifer L. Roizen ◽

Amanda C. Jones ◽

Russell C. Smith ◽

Scott C. Virgil ◽

Brian M. Stoltz

Keyword(s):

Model Studies ◽

Cope Rearrangements ◽

Key Steps

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Reflections on the Cognitive Interviewing Reporting Framework

Methodology ◽

10.1027/1614-2241/a000074 ◽

2013 ◽

Vol 9 (3) ◽

pp. 123-128 ◽

Cited By ~ 1

Author(s):

Gordon Willis ◽

Hennie Boeije

Keyword(s):

Research Design ◽

Cognitive Testing ◽

Level Of Detail ◽

Cognitive Interviewing ◽

Research Groups ◽

Research Project ◽

Reporting Framework ◽

Full Explanation ◽

Key Steps

Based on the experiences of three research groups using and evaluating the Cognitive Interviewing Reporting Framework (CIRF), we draw conclusions about the utility of the CIRF as a guide to creating cognitive testing reports. Authors generally found the CIRF checklist to be usable, and that it led to a more complete description of key steps involved. However, despite the explicit direction by the CIRF to include a full explanation of major steps and features (e.g., research objectives and research design), the three cognitive testing reports tended to simply state what was done, without further justification. Authors varied in their judgments concerning whether the CIRF requires the appropriate level of detail. Overall, we believe that current cognitive interviewing practice will benefit from including, within cognitive testing reports, the 10 categories of information specified by the CIRF. Future use of the CIRF may serve to direct the overall research project from the start, and to further the goal of evaluation of specific cognitive interviewing procedures.

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The development of alternative energy sources: Prospects in Russia and the world

National Interests Priorities and Security ◽

10.24891/ni.16.5.885 ◽

2020 ◽

Vol 16 (5) ◽

pp. 885-904

Author(s):

M.E. Frai

Keyword(s):

Alternative Energy ◽

Systems Approach ◽

Energy Resource ◽

Current Situation ◽

Energy Sources ◽

The Sustainable Development ◽

Energy Complex ◽

Alternative Energy Sources ◽

Governmental Institutions ◽

Key Steps

Subject. The article discusses limited sources of energy nowadays and an ongoing survey of new ones. I focus on fuel and energy complexes worldwide and in Russia. Objectives. The study is to analyze the future use of alternative energy sources in the fuel and energy complex nationwide and worldwide. I review the existing energy sources of the fuel and energy complex in the global and regional markets, specifically the alternative ones. Methods. The study relies upon methods of statistics, analysis and systems approach. Results. The article demonstrates that the fuel and energy complex strongly depends on the current situation in the energy resource market, which is difficult to forecast. If we continue relying on traditional energy resources, we get exposed to some risks affecting the sustainable development of the economy. Russia should diversify the power engineering sector by developing alternative energy sources. The article sets forth the economic rationale for alternative sources and key steps Russia shall make. Conclusions and Relevance. Considering the current situation in the energy balance, alternative energy is what any advanced society seeks for, being supported by manufacturers, governmental institutions, and researchers, though low profitability and high infrastructure costs impede its development. In Russia, these challenges are even more palpable. However, even now Russia is able to find alternative energy solutions. In addition to advantages of alternative energy, which is globally proclaimed, they will also help Russia diversify and update the economic system.

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CO2 Activation on Heterostructures of Bi2O3-Nanocluster Modified TiO2: Promoting the Critical First Step in CO2 Conversion

10.26434/chemrxiv.5917351.v1 ◽

2018 ◽

Cited By ~ 1

Author(s):

Michael Nolan

Keyword(s):

Metal Oxide ◽

Density Functional ◽

Initial Step ◽

Difficult Problem ◽

Carbonate Formation ◽

Structural Distortions ◽

Strong Adsorption ◽

Two Factors ◽

Key Steps ◽

Recent Experimental Work

The conversion of CO2 to fuels is of significant importance in enabling the production of sustainable fuels, contributing to alleviating greenhouse gas emissions. While there are a number of key steps required to convert CO2, the initial step of adsorption and activation by the catalyst is critical. Well-known metal oxides such as oxidised TiO2 or CeO2 are unable to promote this step. In addressing this difficult problem, recent experimental work shows the potential for bismuth-containing materials to activate and convert CO2, but the origin of this activity is not yet clear. Additionally, nanostructures can show enhanced activity towards CO2. In this paper we present density functional theory (DFT) simulations of CO2 activation on heterostructured materials composed of extended rutile and anatase TiO2 surfaces modified with nanoclusters with Bi2O3 stoichiometry. These heterostructures show low coordinated Bi sites in the nanoclusters and a valence band edge that is dominated by Bi-O states. These two factors mean that supported Bi2O3 nanoclusters are able to adsorb and activate CO2. Computed adsorption energies lie in the range of -0.54 eV to -1.01 eV. In these strong adsorption modes, CO2 is activated, in which the molecule bends giving O-C-O angles of 126 - 130o and elongation of C-O distances up to 1.28 Å, with no carbonate formation. The electronic properties show a strong CO2-Bi-oxygen interaction that drives the interaction of CO2 to induce the structural distortions. Bi2O3-TiO2 heterostructures can be reduced to form Bi2+ and Ti3+ species. The interaction of CO2 with this electron-rich, reduced system can produce CO directly, reoxidising the heterostructure or form an activated carboxyl species (CO2-) through electron transfer from the heterostructure to CO2. These results highlight that a semiconducting metal oxide modified with suitable metal oxide nanoclusters can activate CO2, thus overcoming the difficulties associated with the difficult first step in CO2 conversion.

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