Waste-minimised copper-catalysed azide–alkyne cycloaddition in Polarclean as a reusable and safe reaction medium

2018 ◽  
Vol 20 (1) ◽  
pp. 183-187 ◽  
Author(s):  
Lorenzo Luciani ◽  
Emily Goff ◽  
Daniela Lanari ◽  
Stefano Santoro ◽  
Luigi Vaccaro
Keyword(s):  
Reaction Medium ◽  
Water Mixture ◽  
Organic Reaction

Herein we report the first example of a generally useful organic reaction, namely the copper-catalysed azide–alkyne cycloaddition, performed in a Polarclean/water mixture as a reaction medium.

Ionic Liquids for the Synthesis of Five-Membered N,N-, N,N,N- and N,N,N,NHeterocycles

2019 ◽  
Vol 23 (11) ◽  
pp. 1214-1238 ◽  
Author(s):  
Navjeet Kaur ◽  
Pranshu Bhardwaj ◽  
Meenu Devi ◽  
Yamini Verma ◽  
Neha Ahlawat ◽  
...  
Keyword(s):  
Ionic Liquids ◽  
Organic Synthesis ◽  
Heterocyclic Compounds ◽  
Reaction Medium ◽  
Environmental Issues ◽  
Organic Reaction ◽  
Environment Friendly ◽  
The Past ◽  
Area Of Interest ◽  
Major Subject

Due to special properties of ILs (Ionic Liquids) like their wide liquid range, good solvating ability, negligible vapour pressure, non-inflammability, environment friendly medium, high thermal stability, easy recycling and rate promoters etc. they are used in organic synthesis. The investigation for the replacement of organic solvents in organic synthesis is a growing area of interest due to increasing environmental issues. Therefore, ionic liquids have attracted the attention of chemists and act as a catalyst and reaction medium in organic reaction with high activity. There is no doubt that ionic liquids have become a major subject of study for modern chemistry. In comparison to traditional processes the use of ionic liquids resulted in improved, complimentary or alternative selectivities in organic synthesis. The present manuscript reported the synthesis of multiple nitrogen containing five-membered heterocyclic compounds using ionic liquids. This review covered interesting discoveries in the past few years.

ChemInform Abstract: Deep Eutectic Solvents: The Organic Reaction Medium of the Century

ChemInform ◽  
2016 ◽  
Vol 47 (14) ◽  
Author(s):  
Diego A. Alonso ◽  
Alejandro Baeza ◽  
Rafael Chinchilla ◽  
Gabriela Guillena ◽  
Isidro M. Pastor ◽  
...  
Keyword(s):  
Reaction Medium ◽  
Deep Eutectic Solvents ◽  
Organic Reaction

Aqueous Microemulsions as Efficient and Versatile Media for Transition-Metal-Catalyzed Reactions

2013 ◽  
Vol 66 (4) ◽  
pp. 470 ◽  
Author(s):  
Jason G. Taylor ◽  
Jailton Ferrari
Keyword(s):  
Transition Metal ◽  
Organic Solvents ◽  
Reaction Medium ◽  
Environmentally Friendly ◽  
Organic Reaction ◽  
Oil In Water ◽  
Highly Effective ◽  
Transition Metal Catalyzed ◽  
Catalyzed Reactions ◽  
Metal Catalyzed

The search for efficient and versatile reaction medium to perform transition-metal-catalyzed reactions is a continuous challenge to the synthetic community. Organic solvents have been traditionally employed for this task, nevertheless, new environmentally friendly, safe, and economically viable alternatives are still highly sought after. In this context, herein, we present an overview of some interesting applications of aqueous microemulsions (oil-in-water, O/W) for transition metal catalyzed reactions as an alternative and promising aqueous-organic reaction medium that has been found to be a highly effective tool in overcoming some environmental or practical issues presented by traditional organic solvents.

scholarly journals Synthesis of tetraalkyl thiuram disulfides using different oxidants in recycling solvent mixture

2012 ◽  
Vol 18 (1) ◽  
pp. 73-81 ◽  
Author(s):  
Milutin Milosavljevic ◽  
Aleksandar Marinkovic ◽  
Jelena Markovic ◽  
Danijela Brkovic ◽  
Milan Milosavljevic
Keyword(s):  
Isopropyl Alcohol ◽  
Level Structure ◽  
Reaction Medium ◽  
Solvent Mixture ◽  
Azeotropic Mixture ◽  
Water Mixture ◽  
Alcohol Water ◽  
High Yields ◽  
Industrial Level ◽  
Laboratory Synthesis

A new optimized laboratory synthesis of tetraalkyl thiuram disulfides, starting from dialkyl amines and carbon disulfide in presence of three oxidants (hydrogen peroxide, potassium peroxodisulfate and sodium hypochlorite) and appropriate reaction medium: two mixtures of isopropyl alcohol - water used in two consecutive syntheses, was presented in this work. First synthesis was performed in a recycled azeotropic mixture of isopropyl alcohol - water 87.7% - 12.3%, and second in a filtrate obtained after first synthesis, which was a mixture of isopropyl alcohol - water 70.4% - 29.6%. After the second synthesis and filtration, recycled azeotropic mixture isopropyl alcohol - water 87.7% - 12.3% was regenerated from the filtrate by rectification. Considering this, the technology for beneficial use of recycling isopropyl alcohol - water mixture as reaction medium for tetraalkyl thiuram disulfides synthesis was developed. Such concept contributes to extraordinary economical benefit of implemented optimal laboratory synthesis at semi-industrial level. High yields of tetraalkyl thiuram disulfides syntheses were obtained at both laboratory and semiindustrial level. Structure and purity of synthesized compounds were confirmed by elemental analysis, as well as FTIR, 1H and 13C NMR, and MS spectral data.

Polyethylene Glycol as a Green and Biocompatible Reaction Media for the Catalyst Free Synthesis of Organic Compounds

2020 ◽  
Vol 24 (12) ◽  
pp. 1275-1314
Author(s):  
Rezvan Kardooni ◽  
Ali Reza Kiasat
Keyword(s):  
Polyethylene Glycol ◽  
Green Chemistry ◽  
Organic Compounds ◽  
Reaction Medium ◽  
Focal Points ◽  
Organic Reaction ◽  
Considerable Contribution ◽  
Catalyst Free ◽  
Current Review ◽  
Reaction Media

Replacing harmful organic solvents that caused environmental pollution with an alternative medium for the development of ideal synthetic strategies is one of the primary focal points of green chemistry. Utilizing polyethylene glycol (PEG) as a nonvolatile solvent and promotor for the evaluation of safe processes has made a considerable contribution to the reduction of pollution problems. The current review summarizes the recent well-known catalyst-free organic reaction performed in polyethylene glycol as a green and biocompatible reaction medium.

scholarly journals Deep Eutectic Solvents: The Organic Reaction Medium of the Century

2016 ◽  
Vol 2016 (4) ◽  
pp. 612-632 ◽  
Author(s):  
Diego A. Alonso ◽  
Alejandro Baeza ◽  
Rafael Chinchilla ◽  
Gabriela Guillena ◽  
Isidro M. Pastor ◽  
...  
Keyword(s):  
Reaction Medium ◽  
Deep Eutectic Solvents ◽  
Organic Reaction

Ionic Liquids: A Versatile Medium for the Synthesis of Six-membered Two Nitrogen- Containing Heterocycles

2019 ◽  
Vol 23 (1) ◽  
pp. 76-96 ◽  
Author(s):  
Navjeet Kaur
Keyword(s):  
Thermal Stability ◽  
Ionic Liquids ◽  
High Activity ◽  
Organic Synthesis ◽  
Vapour Pressure ◽  
Reaction Medium ◽  
High Thermal Stability ◽  
Organic Reaction ◽  
Major Subject ◽  
The Subject

Due to special properties of ILs (ionic liquids) like their wide liquid range, good solvating ability, negligible vapour pressure, non-inflammability, environmentfriendly medium, high thermal stability, easy recycling and rate promoters etc. they are used in organic synthesis. Therefore, ionic liquids have attracted the attention of chemists and act as a catalyst and reaction medium in organic reaction with high activity. There is no doubt that ionic liquids have become a major subject of study for modern chemistry. More publications in the field have been observed each year, although there is some evidence that this is beginning to plateau at approximately 3500 papers each year. They have been the subject of several major reviews and books, dealing with different applications and aspects of their behavior. Highly efficient methods are explored for the preparation of six-membered two nitrogen-containing heterocycles with the application of IL as a catalyst and reaction medium from 1893 to 2018.

High-voltage cytochemistry for three-dimensional observation of nuclei and calculation of total numbers of nuclear pores in retinal Mueller glia

1990 ◽  
Vol 48 (3) ◽  
pp. 956-957
Author(s):  
H. Ishigooka ◽  
S. Ueno ◽  
L.M. Hjelmeland ◽  
M.B. Landers ◽  
K. Ogawa
Keyword(s):  
Nuclear Envelope ◽  
High Voltage ◽  
Three Dimensional ◽  
Reaction Medium ◽  
Nuclear Pores ◽  
High Voltage Electron Microscopy ◽  
Voltage Electron ◽  
High Voltage Electron ◽  
G6pase Activity ◽  
Mueller Glia

Introduction: We have demonstrated that Glucose-6-phosphatase (G6Pase) activity is localized to the endoplasmic reticulum and nuclear envelope of Mueller glia in the normal and pathological guinea pig retina. Using a combination of this cytochemical technique and high voltage electron microscopy, the distribution of nuclear pores could be clearly observed on the nuclear envelope of Mueller glia because of their anatomical lack of reaction products. This technique was developed to study the three-dimensional structure of nuclei and to calculate total numbers of nuclear pores utilizing a computer graphic analysis system in the normal and pathological retina.Materials and methods: Normal and photocoagulated retina of pigmented adult guinea pigs were perfused with a cold mixture of 0.25% glutaraldehyde and 2% paraformaldehyde in 0.1M cacodylate buffer, and the enucleated globes were hemisected and immersed in the same fixative for 30 min. After sectioning and incubation in the reaction medium for the detection of G6Pase activity by the method of Wachstein-Meisel, the sections were postfixed, dehydrated and embedded in Spurr’s epoxy resin. Serial thick sections (1.0um) were prepared for the observation by a Hitachi high voltage electron microscope (H 1250-M) with an accelerating voltage of 1000 Kv. and pictures were analyzed and three-dimensionally reconstructed by TRI (RATOC Co., Ltd.).

Formation of high temperature phase in flash-evaporated SnSe films

1990 ◽  
Vol 48 (4) ◽  
pp. 698-699
Author(s):  
J.P.S. Hanjra
Keyword(s):  
Thin Films ◽  
Electrical Properties ◽  
Energy Gap ◽  
Dominant Role ◽  
Fine Powder ◽  
High Temperature Phase ◽  
Temperature Phase ◽  
Water Mixture ◽  
Flash Evaporation ◽  
Photovoltaic Applications

Tin mono selenide (SnSe) with an energy gap of about 1 eV is a potential material for photovoltaic applications. Various authors have studied the structure, electronic and photoelectronic properties of thin films of SnSe grown by various deposition techniques. However, for practical photovoltaic junctions the electrical properties of SnSe films need improvement. We have carried out investigations into the properties of flash evaporated SnSe films. In this paper we report our results on the structure, which plays a dominant role on the electrical properties of thin films by TEM, SEM, and electron diffraction (ED).Thin films of SnSe were deposited by flash evaporation of SnSe fine powder prepared from high purity Sn and Se, onto glass, mica and KCl substrates in a vacuum of 2Ø micro Torr. A 15% HF + 2Ø% HNO3 solution was used to detach SnSe film from the glass and mica substrates whereas the film deposited on KCl substrate was floated over an ethanol water mixture by dissolution of KCl. The floating films were picked up on the grids for their EM analysis.

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