scholarly journals Towards a Paradigm Shift in Polar Organometallic Chemistry

2020 ◽  
Vol 74 (9) ◽  
pp. 681-688 ◽  
Author(s):  
Eva Hevia
Keyword(s):  
Organometallic Chemistry ◽  
Synergistic Effects ◽  
Chemical Properties ◽  
Deep Eutectic Solvents ◽  
Chemical Transformations ◽  
Organometallic Reagents ◽  
Cooperative Effects ◽  
Bond Forming ◽  
Synthetic Methodologies ◽  
Metal Reagents

Core tools of synthetic chemistry, polar organometallic reagents (typified by organolithium and Grignard reagents) are used worldwide for constructing compounds, especially aromatic compounds, which are ubiquitous in organic chemistry and thus in numerous commodities essential to everyday life. By isolation and characterisation of key organometallic intermediates, research in our group has led to the design of polar mixed-metal reagents imbued with synergistic effects that display chemical properties and reactivity profiles far exceeding the limits of traditional single-metal reagents. These studies have improved existing, or established new fundamentally important, synthetic methodologies based on either stoichiometric or catalytic reactions. Bimetallic cooperative effects have been demonstrated in an impressive array of important bond forming reactions including deprotonative metallation, transition metal-free C–C bond formation and metal–halogen exchange to name just a few. Towards greener, more sustainable, safer chemical transformations, our group has also pioneered the use of polar organometallic reagents under air and/or with water present using biorenewable solvents such as Deep Eutectic Solvents (DES) and 2-methyl THF. Herein we summarize some of our recent efforts in this intriguing area, which we believe can make inroads towards a step change in the practice and future scope of polar organometallic chemistry.

scholarly journals Organometallic chemical biology: an organometallic approach to bioconjugation

2017 ◽  
Vol 89 (11) ◽  
pp. 1619-1640 ◽  
Author(s):  
Ekaterina V. Vinogradova
Keyword(s):  
Organometallic Chemistry ◽  
Chemical Biology ◽  
Structure And Function ◽  
Future Prospects ◽  
Site Specific ◽  
Organometallic Reagents ◽  
Bond Forming ◽  
Spatially Resolved ◽  
Recent Developments ◽  
And Function

AbstractThis review summarizes the history and recent developments of the field of organometallic chemical biology with a particular emphasis on the development of novel bioconjugation approaches. Over the years, numerous transformations have emerged for biomolecule modification with the use of organometallic reagents; these include [3+2] cycloadditions, C–C, C–S, C–N, and C–O bond forming processes, as well as metal-mediated deprotection (“decaging”) reactions. These conceptually new additions to the chemical biology toolkit highlight the potential of organometallic chemistry to make a significant impact in the field of chemical biology by providing further opportunities for the development of chemoselective, site-specific and spatially resolved methods for biomolecule structure and function manipulation. Examples of these transformations, as well as existing challenges and future prospects of this rapidly developing field are highlighted in this review.

Organocatalyzed Heterocyclic Transformations In Green Media: A Review

2020 ◽  
Vol 07 ◽  
Author(s):  
Neslihan Demirbas ◽  
Ahmet Demirbas
Keyword(s):  
Hydrogen Bonding ◽  
Phase Transfer ◽  
Noncovalent Interactions ◽  
Binding Capacity ◽  
Chemical Transformations ◽  
Organic Transformations ◽  
Phase Transfer Catalysts ◽  
Waste Production ◽  
Synthetic Methodologies ◽  
Organocatalytic Reactions

Background: Since the discovery of metal-free catalysts or organocatalysts about twenty years ago, a number of small molecules with different structures have been using to accelerate organic transformations. With the development of environmental awareness, in order to obtain highly privileged scaffolds, scientists have directed their studies towards the synthetic methodologies which minimize or preferably eliminate the formation of waste, avoid from toxic solvents and reagents and use renewable starting materials as far as possible. Methods: In this connection, the organocatalytic reactions providing efficiency and selectivity for most of case have become an endless topic in organic chemistry since several advantages from both practical and environmental standpoints. Organocatalysts supplying transformation of reactants into products with the least possible waste production have been serving to the concept of green chemistry. Results and Conclusion: Organocatalysts have been classified on the basis of their binding capacity to the substrate with covalently or noncovalent interactions involving hydrogen bonding and electrostatic interaction. Diverse types of small organic compounds including proline and its derivatives, phase-transfer catalysts, (thio)urease, phosphoric acids, sulfones, N-oxides, guanidines, cinchona derivatives, aminoindanol and amino acids have been utilized as hydrogen bonding organocatalysts in different chemical transformations.

scholarly journals Palladium and Copper: Advantageous Nanocatalysts for Multi-Step Transformations

Nanomaterials ◽  
2021 ◽  
Vol 11 (8) ◽  
pp. 1891
Author(s):  
Antonio Reina ◽  
Trung Dang-Bao ◽  
Itzel Guerrero-Ríos ◽  
Montserrat Gómez
Keyword(s):  
Chemical Properties ◽  
Added Value ◽  
Solid Supports ◽  
Nanosized Materials ◽  
Nano Structures ◽  
Liquid Phases ◽  
Wide Range ◽  
Synthetic Methodologies ◽  
Physical And Chemical ◽  
A Current

Metal nanoparticles have been deeply studied in the last few decades due to their attractive physical and chemical properties, finding a wide range of applications in several fields. Among them, well-defined nano-structures can combine the main advantages of heterogeneous and homogenous catalysts. Especially, catalyzed multi-step processes for the production of added-value chemicals represent straightforward synthetic methodologies, including tandem and sequential reactions that avoid the purification of intermediate compounds. In particular, palladium- and copper-based nanocatalysts are often applied, becoming a current strategy in the sustainable synthesis of fine chemicals. The rational tailoring of nanosized materials involving both those immobilized on solid supports and liquid phases and their applications in organic synthesis are herein reviewed.

scholarly journals Design and Synthesis of Fluoro Analogues of Vitamin D

2021 ◽  
Vol 22 (15) ◽  
pp. 8191
Author(s):  
Fumihiro Kawagoe ◽  
Sayuri Mototani ◽  
Atsushi Kittaka
Keyword(s):  
Vitamin D ◽  
Vitamin D3 ◽  
Fluorine Atom ◽  
Chemical Properties ◽  
Molecular Structures ◽  
Physical And Chemical Properties ◽  
Design And Synthesis ◽  
Synthetic Methodologies ◽  
Physical And Chemical ◽  
And Chemical Properties

The discovery of a large variety of functions of vitamin D3 and its metabolites has led to the design and synthesis of a vast amount of vitamin D3 analogues in order to increase the potency and reduce toxicity. The introduction of highly electronegative fluorine atom(s) into vitamin D3 skeletons alters their physical and chemical properties. To date, many fluorinated vitamin D3 analogues have been designed and synthesized. This review summarizes the molecular structures of fluoro-containing vitamin D3 analogues and their synthetic methodologies.

scholarly journals The influence of biochar on the content of carbon and the chemical transformations of fallow and grassland humic acids

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Marta Cybulak ◽  
Zofia Sokołowska ◽  
Patrycja Boguta
Keyword(s):  
Humic Acids ◽  
Chemical Properties ◽  
Soil Samples ◽  
Low Molecular Weight ◽  
Organic Carbon Content ◽  
Chemical Transformations ◽  
Limited Information ◽  
Grassland Soils ◽  
Low Degree ◽  
Humification Degree

AbstractThere is limited information regarding the effect of biochar (BioC) on the fertility of fallow and grassland soils, as well as on the properties of their humic acids (HAs). The objective of this study was to evaluate with a 3-year field experiment the influence of BioC on the organic matter (OM) in Haplic Luvisol. BioC (obtained via wood waste pyrolysis at 650 °C) was applied to the soil of subplots under fallow and grassland at doses of 0, 1, 2 and 3 kg m−2. The soil samples were collected eight times. The physicochemical properties were determined for the soil and BioC by analysing the density, pH, surface charge, ash, and organic carbon content. Based on the changes in the structure of the HAs and their quantity in the soils, the chemical properties of the HAs were determined. The maximum BioC dose caused an increase in the content of Corg and HAs. BioC did not influence the humification degree coefficients of the HAs originated from fallow, whereas in the grassland, there were significant changes observed in these coefficient values, indicating that BioC may stimulate and accelerate the humification process of soil HAs. Increasing the BioC doses caused an increase in the soil’s HA content, suggesting an increase in soil sorption capacity. The fluorescence data showed BioC addition to the soil caused an increase in the number of structures characterised by low molecular weight and a low degree of humification.

Sēra dioksīda fizikāli ķīmisko īpašību pielietojums jaunu organiskās sintēzes metožu izstrādē / Development of New Organic Synthesis Methods Based on Physico-Chemical Properties of Sulfur Dioxide

2021 ◽  
Author(s):  
◽  
Krista Gulbe
Keyword(s):  
Organic Synthesis ◽  
Chemical Properties ◽  
Coupling Reaction ◽  
Synthetic Methods ◽  
Synthesis Methods ◽  
Chemical Transformations ◽  
Scientific Publications ◽  
Cross Coupling Reaction ◽  
Aryl Acetylenes ◽  
The Republic

The Doctoral Thesis has been prepared as a collection of thematically related scientific publications comprising five publications in the SCI journals, one patent of the Republic of Latvia, and one application for patent of the Republic of Latvia. We have carried out fundamental research on the applications of SO2 as a solvent and reagent in organic synthesis. We have developed several novel synthetic methods that represent the use of liquid SO2 as a solvent for chemical transformations that proceed via carbenium ion intermediates: a) hydration of aryl acetylenes; b) hydrohalogenation of aryl acetylenes; c) ring opening of methylenecyclopropanes with halides; d) glycosylation with glycosyl fluorides. By employing DABSO as an SO2 surrogate, we have also discovered the catalytic activity of Ru(II) complexes towards sulfonylative cross coupling reaction. This finding has been applied for the synthesis of sulfonyl derived compounds.

scholarly journals A review on the bio-functional roles of phospholipids from marine resources

Food Research ◽  
2021 ◽  
Vol 5 (5) ◽  
pp. 1-16
Author(s):  
M. Haq ◽  
S. Suraiya
Keyword(s):  
Synergistic Effects ◽  
Chemical Properties ◽  
Functional Roles ◽  
Functional Activities ◽  
Marine Phospholipids ◽  
Liver Functions ◽  
Anti Inflammatory ◽  
Unique Chemical

Marine phospholipids (PLs) rich in ω-3 polyunsaturated fatty acids (ω-3 PUFAs) have drawn keen interest recently among researchers and consumers and could be assumed as a “miracle drug”. Substantial amount of EPA and DHA, amazing and unique chemical properties and super bio-functional activities of marine PLs make it superior compared to terrestrial PLs, which lack long chain ω-3 PUFAs. Many comparative studies revealed that marine PLs showed higher health beneficial activities compared to PLs obtained from land sources. Marine PLs are not only beneficial in containing a high amount of ω-3 PUFAs but also in absorbing and assimilating ω-3 PUFAs in different tissues. Synergistic effects of PL compounds and ω-3 PUFAs in marine PLs showed super bio-functional performances like anti-atherosis and cardioprotective, anti-inflammatory, neuroprotective, immunological, and liver functions. A number of in vivo and in vitro studies on the administration of marine PLs extracted from fishes, mollusks, crustaceans, echinoderms reduced triacylglycerol (TAG) level and enhanced cardioprotective functions, demonstrated anti-inflammatory activity, reduced cell proliferation and tumor, increased cognitive functions and memory, and prevented hepatic damages. Therefore, this review paper provides detailed accounts on the present research status of critical biological and nutritional functions of marine ω-3 PUFAs rich phospholipids focusing on the origin, animal models, treatment, and roles.

Organometallic chemistry on rhodaheteroborane clusters: reactions with bidentate phosphines and organotransition metal reagents

2003 ◽  
Vol 17 (6-7) ◽  
pp. 409-420 ◽  
Author(s):  
Oleg Volkov ◽  
Ramón Macías ◽  
Nigam P. Rath ◽  
Lawrence Barton
Keyword(s):  
Organometallic Chemistry ◽  
Metal Reagents

The properties and behavior of α-pinene secondary organic aerosol particles exposed to ammonia under dry conditions

2017 ◽  
Vol 19 (9) ◽  
pp. 6497-6507 ◽  
Author(s):  
David M. Bell ◽  
Dan Imre ◽  
Scot T. Martin ◽  
Alla Zelenyuk
Keyword(s):  
Secondary Organic Aerosol ◽  
Chemical Properties ◽  
Particle Morphology ◽  
Organic Aerosol ◽  
Chemical Transformations ◽  
Physical And Chemical Properties ◽  
Dry Conditions ◽  
And Behavior ◽  
Physical And Chemical ◽  
And Chemical Properties

Chemical transformations and aging of secondary organic aerosol (SOA) particles can alter their physical and chemical properties, including particle morphology.

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