scholarly journals Merging shuttle reactions and paired electrolysis for reversible vicinal dihalogenations

Science ◽  
2021 ◽  
Vol 371 (6528) ◽  
pp. 507-514
Author(s):  
Xichang Dong ◽  
Johannes L. Roeckl ◽  
Siegfried R. Waldvogel ◽  
Bill Morandi
Keyword(s):  
Soil Samples ◽  
Waste Material ◽  
Environmental Persistence ◽  
Graphite Electrodes ◽  
Elemental Chlorine ◽  
Modern Chemistry ◽  
Wide Range ◽  
Commodity Chemicals ◽  
Synthetic Intermediates ◽  
Halogenated Pollutants

Vicinal dibromides and dichlorides are important commodity chemicals and indispensable synthetic intermediates in modern chemistry that are traditionally synthesized using hazardous elemental chlorine and bromine. Meanwhile, the environmental persistence of halogenated pollutants necessitates improved approaches to accelerate their remediation. Here, we introduce an electrochemically assisted shuttle (e-shuttle) paradigm for the facile and scalable interconversion of alkenes and vicinal dihalides, a class of reactions that can be used both to synthesize useful dihalogenated molecules from simple alkenes and to recycle waste material through retro-dihalogenation. The reaction is demonstrated using 1,2-dibromoethane, as well as 1,1,1,2-tetrachloroethane or 1,2-dichloroethane, to dibrominate or dichlorinate, respectively, a wide range of alkenes in a simple setup with inexpensive graphite electrodes. Conversely, the hexachlorinated persistent pollutant lindane could be fully dechlorinated to benzene in soil samples using simple alkene acceptors.

Divergent Electrolysis for the Controllable Coupling of Thiols with 1,2-Dichloroethane: a Mild Approach to Sulfide and Sulfoxide

2022 ◽  
Author(s):  
Fei Ling ◽  
Tao Liu ◽  
Chao Xu ◽  
Jiaying He ◽  
Wangqin Zhang ◽  
...  
Keyword(s):  
Metal Catalysts ◽  
Modern Chemistry ◽  
Commodity Chemicals ◽  
Synthetic Intermediates

Organosulfurs are important commodity chemicals and indispensable synthetic intermediates in modern chemistry that traditionally synthesized using metal catalysts, oxidants or strong bases, which caused numerous issues of environment pollutions. The...

Regioselective Synthesis of Indenones via Nickel-Catalyzed Larock Annulations

2021 ◽  
Author(s):  
Feipeng Liu ◽  
Yongjie Li ◽  
Xuchao Wang ◽  
Qing Qiang ◽  
Zijuan Yan ◽  
...  
Keyword(s):  
Regioselective Synthesis ◽  
Wide Range ◽  
Highly Effective ◽  
Synthetic Intermediates

We present herein a highly effective nickel-catalyzed Larock annulations of substituted 2-formylphenyl trifluoromethanesulfonate with alkynes to provide access to a wide range of indenones that are valuable synthetic intermediates for...

Diversity and distribution of entomopathogenic nematodes in Chile

Nematology ◽  
2010 ◽  
Vol 12 (6) ◽  
pp. 915-928 ◽  
Author(s):  
Steve Edgington ◽  
Alan G. Buddie ◽  
Dave Moore ◽  
Andrés France ◽  
Loreto Merino ◽  
...  
Keyword(s):  
Entomopathogenic Nematodes ◽  
Atacama Desert ◽  
Soil Samples ◽  
Ex Situ ◽  
Steinernema Feltiae ◽  
Coastal Zones ◽  
The South ◽  
Wide Range ◽  
Natural Hosts ◽  
Northern Regions

Abstract A systematic programme of surveys for entomopathogenic nematodes (EPN) was done in Chile between 2006 and 2008. The survey spanned the principal ecosystems of mainland Chile as well as a number of islands, and covered a wide range of habitats including the Atacama Desert, Andean Altiplano, temperate rainforests and subpolar territory. Nearly 1400 soil samples were collected, of which 7% were positive for EPN. Of 101 EPN isolates obtained, 94 were Steinernema spp. and seven were Heterorhabditis sp. Of the 94 Steinernema isolates, 39 were identified as Steinernema feltiae, the remainder being distributed between two new species, S. unicornum (52 records) and S. australe (three records). The Heterorhabditis isolates, all designated as Heterorhabditis sp.1, are referred to herein as H. cf. safricana. Steinernema feltiae and S. unicornum were collected predominately in the south of Chile and were obtained from a range of habitats, including forests, open grassland, montane soils and coastal zones; neither species was recovered from the far north of the country (viz., desert soils in the Norte Grande region). Steinernema australe was found in only three soil samples, all from humid, cool, coastal localities in the south. Heterorhabditis cf. safricana was recovered from the northern regions, with most isolates found in or on the periphery of the Atacama Desert; they were not recovered from cooler, more humid regions of southern Chile. Molecular information indicated there were two subgroups of both S. unicornum and S. feltiae, with a geographical, intraspecific split of subgroups between the most southerly and the more central survey zones. All isolates were collected by ex situ baiting with waxmoth larvae and the natural hosts are unknown.

scholarly journals Relationship between the mass of organic matter and carbon in soil

2008 ◽  
Vol 51 (2) ◽  
pp. 263-269 ◽  
Author(s):  
Silmara R. Bianchi ◽  
Mario Miyazawa ◽  
Edson L. de Oliveira ◽  
Marcos Antonio Pavan
Keyword(s):  
Organic Matter ◽  
Soil Organic Matter ◽  
Organic Carbon ◽  
Soil Depth ◽  
Soil Surface ◽  
Soil Samples ◽  
Loss On Ignition ◽  
Oxidation Degree ◽  
Wide Range

The quantity of soil organic matter (SOM) was estimated through the determination of soil organic carbon (SOC) times a factor, which assumes that 58% of the SOM was formed by carbon. A number of soil samples with wide range of SOC content collected in the state of Paraná, Brazil were evaluated in the laboratory. SOC was measured by Walkley-Black method and the total SOM by loss on ignition. The SOC was positively correlated with SOM. The SOM/SOC ratio varied from 1.91 to 5.08 for the soils. It shows that Brazilian SOM has greater oxidation degree. Although, the SOM and SOC decreased with soil depth the SOM/SOC ratio increased. It showed that SOM in the subsoil contained more oxygen but less carbon than the SOM in the upper soil surface. The CEC/SOC also increased with depth indicating that the functional groups of the SOM increased per unity of carbon.

scholarly journals Merging Shuttle Reactions and Paired Electrolysis: E-Shuttle Unlocks Reversible Halogenations

2020 ◽  
Author(s):  
Xichang Dong ◽  
Johannes L. Röckl ◽  
Siegfried R. Waldvogel ◽  
Bill Morandi
Keyword(s):  
Organic Chemistry ◽  
Flame Retardants ◽  
Environmental Pollutant ◽  
Halogen Bonds ◽  
Recycling Process ◽  
New Horizons ◽  
Synthetic Intermediates ◽  
Halogenated Pollutants ◽  
Hazardous Compounds ◽  
Different Soils

<p>Polyhalogenated molecules have found widespread applications as flame retardants, pest-control agents, polymers and pharmaceuticals. They also serve as versatile synthetic intermediates in organic chemistry due to the inherent reactivity of carbon-halogen bonds. Despite these attractive features, the preparation of polyhalogenated molecules still mainly relies on the use of highly toxic and corrosive halogenating reagents, such as Cl<sub>2</sub> and Br<sub>2</sub>, which are hazardous compounds to transport, store, and handle. Moreover, the use of such highly reactive reagents inherently makes the development of the reverse reactions, <i>retro</i>-dihalogenations, highly challenging, despite their potential for the recycling of persistent halogenated pollutants. Here, we introduce an electrochemically-assisted shuttle<i> (e-shuttle)</i> paradigm for the facile and scalable interconversion of alkenes and vicinal dihalides, a class of reactions which can be used both to synthesize useful polyhalogenated molecules from simple alkenes and to recycle waste material through <i>retro</i>-dihalogenation. The power of this reaction is best highlighted by an example, in which different soils contaminated with a persistent environmental pollutant (Lindane), could be directly used as Cl<sub>2</sub>-donors for the transfer dichlorination of simple feedstock alkenes, merging a recycling process with a synthetically relevant dichlorination reaction. We further demonstrate that this paired electrolysis-enabled shuttle protocol, which uses a simple setup and inexpensive electrodes, is applicable to four different, synthetically useful transfer halogenation reactions, and can be readily scaled-up to a decagram scale. In a broader context, the symbiotic merging of shuttle reactions and electrochemistry introduced in this work opens new horizons for safer transfer functionalization reactions that will address important challenges across the molecular sciences.</p> <div><br><div> </div> </div>

scholarly journals A new record of Actinobacteria isolated from soil in Jerusalem and their enzymatic potential

F1000Research ◽  
2015 ◽  
Vol 4 ◽  
pp. 11
Author(s):  
Samira R. Mansour ◽  
Ahmed M. Abdel-Azeem ◽  
Samy Salem Soliman Abo-Deraz
Keyword(s):  
New Record ◽  
Soil Samples ◽  
Industrial Scale ◽  
Terrestrial Environment ◽  
Cellulase Enzyme ◽  
Wide Range ◽  
Promising Source

Actinobacteria are well recognized for their bioactive compounds.They are considered as a promising source of wide range of important enzymes, some of which are produced on an industrial scale. In this study, 35 isolates of actinomycetes were isolated from soil samples collected in the area of Al-Aqsa Mosque in Jerusalem, Israel. To our knowledge, this is the first study of actinomycetes from this terrestrial environment. The efficiency of the isolated actinobacteria in the production of amylase, cellulase, protease, tyrosinase, lipase, catalase and phosphatase was studied. Isolates obtained showed some activity and other completely failed to produce such enzymes. From total 35 isolates, only three isolates (8.6%) showed ability to produce protease, four isolates (11.4%) for lipase, five isolates (14.3%) for tyrosinase and two isolates (5.7%) for phosphatase enzymes. However, all isolates were positive for amylase and catalase enzymes; vice versa for cellulase enzyme all isolates failed to degrade cellulose in the form of carboxymethylcellulose.

scholarly journals Optimization of Pigment Production by Micrococcus and Arthrobacter species Isolated from Soil and Water

2021 ◽  
Vol 12 (3) ◽  
pp. 1902-1907
Author(s):  
Sanchita Choubey ◽  
Sneha Vittal Chapade ◽  
Supriya Ashok Garud
Keyword(s):  
Anticancer Agents ◽  
Antibacterial Agent ◽  
Soil Samples ◽  
Synthetic Dyes ◽  
Wide Range ◽  
Water And Soil Samples ◽  
Anti Oxidant ◽  
Arthrobacter Species ◽  
Soil And Water ◽  
Bacterial Pigments

A pigment is a substance that is substantially used in different industries that come in a wide range of coloration and few of which are soluble in water. Bacterial pigments have many applications in the modern day life. Some microorganisms have the characteristics feature to produce pigments which may additionally beneficial us in identification. Bacterial pigments have larger compatibility and greater biodegradability with the environment. Nontoxic nature of pigment produced with the aid of a huge range of microorganisms make them ecofriendly for use in foodstuff, dye, cosmetics, pharmacy and different industrial purposes. Pigments of bacteria provide various advantages compared to synthetic dyes. They are biodegradable in nature, easy to extract, easily available, cheaper substrates needed. The pigment produced by the bacteria can be used as anticancer agents, antibacterial agent and anti-proliferative agents. The object of the existing find out about was once to isolated  pigment producing microorganism from water and soil samples and explores their properties. Based on their morphological and biochemical characteristics, they have been recognized as Micrococcus and Arthrobacter. The pigment isolated from bacterial spp. is used for the antimicrobial activity, anti-oxidant recreation and for optimization of pH, temperature and NaCl. It was once concluded that water and soil have various microorganisms and they have the capacity of producing pigments.

Molecular-level environments of intercalated chloroaluminate anions in rechargeable aluminum-graphite batteries revealed by solid-state NMR spectroscopy

2020 ◽  
Vol 8 (31) ◽  
pp. 16006-16017
Author(s):  
Jeffrey H. Xu ◽  
Ankur L. Jadhav ◽  
Damon E. Turney ◽  
Robert J. Messinger
Keyword(s):  
Solid State ◽  
Nmr Spectroscopy ◽  
Dft Calculations ◽  
Solid State Nmr ◽  
Molecular Level ◽  
Mas Nmr ◽  
Graphite Electrodes ◽  
Solid State Nmr Spectroscopy ◽  
Intercalated Graphite ◽  
Wide Range

Solid-state 27Al MAS NMR spectroscopy and DFT calculations reveal that intercalated AlCl4− anions exhibit a wide range of molecular geometries and environments, establishing that the intercalated graphite electrodes exhibit high extents of disorder.

Isozyme Variability in Field Populations of Phytophthora cinnamomi in Australia

1988 ◽  
Vol 36 (3) ◽  
pp. 355 ◽  
Author(s):  
KM Old ◽  
MJ Dudzinski ◽  
JC Bell
Keyword(s):  
Sexual Reproduction ◽  
Phytophthora Cinnamomi ◽  
Soil Samples ◽  
Mating Types ◽  
South Eastern ◽  
Enzyme Loci ◽  
Eastern Australia ◽  
Wide Range ◽  
Isozyme Variability ◽  
South Eastern Australia

Isozyme characteristics of 280 isolates from populations of Phytophthora cinnamomi in native veg- etation in six locations in south-eastern Australia were examined at 19 enzyme loci. No new enzyme genotypic arrays were identified as compared with earlier samplings. This work indicates that the low variability for P. cinnamomi in Australia obtained in earlier work, from separate isolates in a wide range of locations, is paralleled in detailed population samples in south-eastern Australia. At one location, A1 and A2 mating types coexisted in soil samples. The lack of recombinants in these population samples suggests an absence of sexual reproduction in the field.

Impact of UPLC-MS in Food and Drug/Metabolite Analysis

2020 ◽  
Vol 17 (1) ◽  
pp. 10-30
Author(s):  
Ankit Semwal ◽  
Raghav Dogra ◽  
Kritika Verma ◽  
Rohit Bhatia
Keyword(s):  
Mass Spectrometry ◽  
High Pressure ◽  
Soil Samples ◽  
Metabolite Analysis ◽  
Drug Metabolites ◽  
Ultra High Pressure ◽  
Drug Metabolite ◽  
Wide Range ◽  
Analytical Research ◽  
Distinguishing Features

The hyphenation of Ultra-Performance Liquid performance (UPLC) with mass spectrometry (MS) has emerged as a powerful tool in analytical research due to its advanced sensitivity, resolution and speed. Its advanced instrumentation, specialized columns, separation at ultra-high pressure and sophisticated software are the distinguishing features as compared to the traditional separating techniques. It has a wide range of applications in various fields such as analysis of food stuffs, drug metabolites, beverages, toxicology, soil samples and micronutrient analysis. In the present compilation, authors have highlighted the applicability of UPLC-MS in the analysis of food stuffs and drug metabolites along with the various optimized analytical conditions and obtained results.

Sign in / Sign up

Export Citation Format

Share Document