scholarly journals A practically simple, catalyst free and scalable synthesis of N-substituted ureas in water

RSC Advances ◽  
2018 ◽  
Vol 8 (38) ◽  
pp. 21585-21595 ◽  
Author(s):  
Lata Tiwari ◽  
Varun Kumar ◽  
Bhuvesh Kumar ◽  
Dinesh Mahajan
Keyword(s):  
Organic Solvent ◽  
Catalyst Free ◽  
Wide Range ◽  
Scalable Synthesis

A wide range of amines can be converted to N-substituted ureas using KOCN and aq. HCl without heating, organic solvent or catalyst.

scholarly journals Synthesis of photoreactive solvent-free acrylic pressure-sensitive adhesives in the recovered system

2007 ◽  
Vol 9 (2) ◽  
pp. 5-9 ◽  
Author(s):  
Roland Milker ◽  
Zbigniew Czech ◽  
Marta Wesołowska
Keyword(s):  
Organic Solvent ◽  
Solvent Free ◽  
The Novel ◽  
Pressure Sensitive Adhesive ◽  
Adhesive Film ◽  
Pressure Sensitive Adhesives ◽  
Pressure Sensitive ◽  
Wide Range ◽  
Protective Films ◽  
New Type

Synthesis of photoreactive solvent-free acrylic pressure-sensitive adhesives in the recovered system The present paper discloses a novel photoreactive solvent-free acrylic pressure-sensitive adhesive (PSA) systems, especially suitable for the so much adhesive film applications as the double-sided, single-sided or carrier-free technical tapes, self-adhesive labels, protective films, marking and sign films and wide range of medical products. The novel photoreactive solvent-free pressure-sensitive adhesives contain no volatile organic compounds (residue monomers or organic solvent) and comply with the environment and legislation. The synthesis of this new type of acrylic PSA is conducted in common practice by solvent polymerisation. After the organic solvent are removed, there remains a non-volatile, solvent-free highly viscous material, which can be processed on a hot-melt coating machine at the temperatures of about 100 to 140°C.

Determination of Fungicides in Fruit Juice by Ultrasound-Assisted Dispersive Liquid–Liquid Microextraction Based on Solidification of Floating Organic Solvent Droplets Followed by High Performance Liquid Chromatography

2014 ◽  
Vol 97 (1) ◽  
pp. 183-187 ◽  
Author(s):  
Run-Zhen Fan ◽  
Congyun Liu ◽  
Wenqing Jiang ◽  
Xiaonan Wang ◽  
Fengmao Liu
Keyword(s):  
Organic Solvent ◽  
High Performance ◽  
Fruit Juice ◽  
Enrichment Factors ◽  
Wide Range ◽  
Separation And Preconcentration ◽  
Ultrasound Assisted ◽  
Dispersive Liquid Liquid Microextraction ◽  
Liquid Microextraction

Abstract Ultrasound-assisted dispersive liquid–liquid microextraction (UA-DLLME) based on solidification of the floating organic solvent droplets (SFO) combined with HPLC was used for determination of five fungicides in fruit juice samples. 1-Dodecanol, which has a low density and low toxicity, was used as the extraction solvent in UA-DLLME. The solidification of floating organic dropletsfacilitates the transfer of analytes from the aqueous phase to the organic phase. This method was easy, quick, inexpensive, precise, and linear over a wide range. Under the optimized conditions, the enrichment factors for a 5 mL fruit juice sample were 25 to 56, and the LODs for the five fungicides ranged from 5 to 50 μg/L. The average recoveries ranged from 71.8 to 118.2% with RSDsof 0.9 to 13.9%. Application of the DLLME-SFO technique allows successful separation and preconcentration of the fungicides at a low concentration level in fruit juice samples.

scholarly journals A novel three-component reaction between isocyanides, alcohols or thiols and elemental sulfur: a mild, catalyst-free approach towards O-thiocarbamates and dithiocarbamates

2019 ◽  
Vol 15 ◽  
pp. 1523-1533 ◽  
Author(s):  
András György Németh ◽  
György Miklós Keserű ◽  
Péter Ábrányi-Balogh
Keyword(s):  
Elemental Sulfur ◽  
Building Blocks ◽  
Reaction Conditions ◽  
One Pot ◽  
Catalyst Free ◽  
Synthetic Procedure ◽  
Three Component Reaction ◽  
Wide Range ◽  
Organic Chemist ◽  
The One

A new multicomponent reaction has been developed between isocyanides, sulfur and alcohols or thiols under mild reaction conditions to afford O-thiocarbamates and dithiocarbamates in moderate to good yields. The one-pot reaction cascade involves the formation of an isothiocyanate intermediate, thus a catalyst-free synthesis of isothiocyanates, as valuable building blocks from isocyanides and sulfur is proposed, as well. The synthetic procedure suits the demand of a modern organic chemist, as it tolerates a wide range of functional groups, it is atom economic and easily scalable.

Catalyst-Free Synthesis of Diastereomerically Pure 3-Sulfonyl­azetidin-2-ones via Microwave-Assisted Tandem Wolff Rearrangement–Staudinger Cycloaddition

Synthesis ◽  
2020 ◽  
Author(s):  
Mikhail Krasavin ◽  
Judith Synofzik ◽  
Olga Bakulina ◽  
Olga Balabas ◽  
Dmitry Dar’in
Keyword(s):  
Drug Design ◽  
Single Crystal ◽  
Wolff Rearrangement ◽  
X Ray ◽  
Design And Optimization ◽  
X Ray Crystallography ◽  
Microwave Assisted ◽  
Catalyst Free ◽  
Relative Stereochemistry ◽  
Wide Range

A wide range of α-diazo-β-ketosulfones have been applied to thermally promoted tandem Wolff rearrangement – Staudinger [2+2] cycloaddition with imines to give polysubstituted β-lactam sulfones. Dia­stereomerically pure syn-diastereomers were obtained in good yields and the relative stereochemistry was confirmed by single-crystal X-ray crystallography. These findings significantly expand the scope of this transformation, in contrast to substantial limitations reported previously. Moreover, this methodology enables flexible exploration of new substitution patterns around the privileged β-lactam core for drug design and optimization.

scholarly journals Optimized and scalable synthesis of magnetic nanoparticles for RNA extraction in response to developing countries' needs in the detection and control of SARS-CoV-2

2020 ◽  
Author(s):  
Julio C. Chacón-Torres ◽  
C. Reinoso ◽  
Daniela G. Navas-Leon ◽  
S. Briceño ◽  
G. González
Keyword(s):  
Magnetic Nanoparticles ◽  
Low Cost ◽  
Rna Extraction ◽  
International Health ◽  
Private Companies ◽  
Wide Range ◽  
Chemical Availability ◽  
Scalable Synthesis ◽  
The Cost ◽  
And Control

Abstract Ecuador is one of the most affected countries, with the coronavirus disease 2019 (COVID-19) infection, in Latin America derived from an ongoing economic crisis. One of the most important methods for COVID-19 detection is the use of techniques such as real time RT- PCR based on a previous extraction/purification of RNA procedure from nasopharyngeal cells using functionalized magnetic nanoparticles (MNP). This technique allows the processing of ~10,000 tests per day in private companies and around hundreds per day at local Universities guaranteeing to reach a wide range of the population. However, the main drawback of this method is the need for specialized MNP with a strong negative charge for the viral RNA purification to detect the existence of the SARS-CoV-2 virus. Here we present a simplified low cost method to produce 10 g of nanoparticles in 100 mL of solution that was scaled to one litter by parallelizing the process 10 times in just two days and allowing for the possibility of making ~50,000 COVID-19 tests. This communication helps in reducing the cost of acquiring MNP for diverse biomolecular applications supporting developing country budgets constraints and chemical availability specially during the COVID-19 International Health Emergency.

Organic solvent- and catalyst-free Baeyer–Villiger oxidation of levoglucosenone and dihydrolevoglucosenone (Cyrene®): a sustainable route to (S)-γ-hydroxymethyl-α,β-butenolide and (S)-γ-hydroxymethyl-γ-butyrolactone

2018 ◽  
Vol 20 (11) ◽  
pp. 2455-2458 ◽  
Author(s):  
Guillaume Bonneau ◽  
Aurélien A. M. Peru ◽  
Amandine L. Flourat ◽  
Florent Allais
Keyword(s):  
Organic Solvent ◽  
Catalyst Free ◽  
One Step ◽  
Villiger Oxidation

Aqueous H2O2-mediated Baeyer–Villiger oxidation of levoglucosenone provides valuable chiral lactone HBO in one step without an organic solvent, catalyst nor acid.

An atmosphere and light tuned highly diastereoselective synthesis of cyclobuta/penta[b]indoles from aniline-tethered alkylidenecyclopropanes with alkynes

2018 ◽  
Vol 54 (23) ◽  
pp. 2870-2873 ◽  
Author(s):  
Bo Cao ◽  
Yin Wei ◽  
Min Shi
Keyword(s):  
Indole Derivatives ◽  
Diastereoselective Synthesis ◽  
Free Atmosphere ◽  
Catalyst Free ◽  
Wide Range

A catalyst-free atmosphere and light tuned highly diastereoselective synthesis of cyclobuta/penta[b]indoles from aniline-tethered alkylidenecyclopropanes and alkynes was developed, which provided a wide range of cyclobuta- and cyclopenta[b]indole derivatives in good yields.

Highly efficient one-pot synthesis of trisubstituted imidazoles under catalyst-free conditions

2012 ◽  
Vol 90 (2) ◽  
pp. 195-198 ◽  
Author(s):  
Najmadin Azizi ◽  
Nairreh Dado ◽  
Alireza Khajeh Amiri
Keyword(s):  
Ammonium Acetate ◽  
High Yield ◽  
One Pot ◽  
Catalyst Free ◽  
Highly Efficient ◽  
One Pot Synthesis ◽  
Scalable Synthesis ◽  
Simple Atom

Operationally simple, atom economical, and scalable synthesis of 2,4,5-trisubstituted imidazoles from benzil, aldehydes, and ammonium acetate is shown to proceed readily in methanol with high yield. The scope of the reaction is quite broad; a variety of aromatic and aliphatic activated and unactivated aldehydes have all been shown to be viable substrates for this reaction. Excellent yields and purity were obtained by washing the products with hot ethanol.

Michael Addition of Aryl Thiols to 3-(2,2,2-Trifluoroethylidene)Oxindoles under Catalyst-Free Conditions: The Rapid Synthesis of Sulfur-Containing Oxindole Derivatives

2018 ◽  
Vol 42 (4) ◽  
pp. 210-214
Author(s):  
Bo Chen ◽  
Jiaheng Lei ◽  
Junling Zhao
Keyword(s):  
Michael Addition ◽  
Room Temperature ◽  
Rapid Synthesis ◽  
Efficient Catalyst ◽  
Mild Conditions ◽  
Catalyst Free ◽  
Wide Range ◽  
High Yields ◽  
The Michael Addition ◽  
Sulfur Containing

A mild and efficient catalyst-free method for the rapid synthesis at room temperature of 3-thiomethylated oxindole derivatives has been achieved via the Michael addition of aryl thiols to ring and 1-substituted 3-(2,2,2-trifluoroethylidene)oxindoles in dichloromethane. The method was applicable to a wide range of thiols and variously substituted 3-(2,2,2-trifluoroethylidene)oxindoles under mild conditions as demonstrated by the synthesis in high yields with good diastereoselectivities of 30 3-thiomethylated oxindoles bearing a trifluoromethyl group.

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