A Bench-Stable Vilsmeier Reagent for in situ Alcohol Activation: Synthetic Application in the Synthesis of 2-Amino-2-Thiazolines

Synlett ◽  
2017 ◽  
Vol 28 (20) ◽  
pp. 2845-2850 ◽  
Author(s):  
Michael Corbett ◽  
Seb Caille
Keyword(s):  
Functional Group ◽  
High Efficiency ◽  
Methyl Sulfate ◽  
Vilsmeier Reagent ◽  
In Situ Activation ◽  
Alcohol Activation ◽  
Activation Of Alcohols ◽  
Synthetic Application ◽  
Direct Condensation

A robust, chemoselective direct condensation/cyclization of thioureas and amino alcohols is described. Employing a bench-stable Vilsmeier reagent, methoxymethylene-N,N-dimethyliminium methyl sulfate, the selective in situ activation of alcohols is achieved with high efficiency and broad functional-group tolerance. The reversible interaction of the Vilsmeier reagent with substrate was key to the success of this activation strategy.

Efficient Synthesis of Diverse 5-Thio- or 5-Selenotriazoles: One-Pot Multicomponent Reaction from Elemental Sulfur or Selenium

Synthesis ◽  
2019 ◽  
Vol 51 (22) ◽  
pp. 4170-4182 ◽  
Author(s):  
Lin-Lin Zhang ◽  
Ya-Ting Li ◽  
Ting Gao ◽  
Sha-Sha Guo ◽  
Bei Yang ◽  
...  
Keyword(s):  
Elemental Sulfur ◽  
Functional Group ◽  
High Efficiency ◽  
Efficient Synthesis ◽  
One Pot ◽  
Mild Conditions ◽  
Ligand Free ◽  
Multistep Reaction ◽  
Easy Operation

A sequential multistep reaction toward 5-thio- or 5-selenotriazoles has been established by generation of both copper(I) triazolides and sulfenylating or selenylating agents in situ, starting from elemental sulfur or selenium. This reaction features mild conditions, readily available and broad-scope substrates, good functional group compatibility, high efficiency and regioselectivity, easy operation, and ligand-free CuI.

Acid-Responsive Endosomolytic Polymeric Nanoparticles with Amplification of Intracellular Oxidative Stress for Prodrug Delivery and Activation

2021 ◽  
Author(s):  
Nannan Lu ◽  
Longchang Xi ◽  
Zengshi Zha ◽  
Yuheng Wang ◽  
Xinghua Han ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Anticancer Drugs ◽  
High Efficiency ◽  
Polymeric Nanoparticles ◽  
In Situ Activation ◽  
Intracellular Oxidative Stress

Prodrug strategy especially in the field of chemotherapy of cancers possesses significant advantages to reduce the side toxicity of anticancer drugs. However, high-efficiency delivery and in situ activation of prodrugs...

A Photoactivatable α5β1-Specific Integrin Ligand

2018 ◽  
Author(s):  
Roshna Vakkeel ◽  
Aleeza Farrukh ◽  
Aranzazu del Campo
Keyword(s):  
Cellular Response ◽  
Light Exposure ◽  
Matrix Composition ◽  
Cellular Behavior ◽  
Dynamic Variations ◽  
In Situ Activation ◽  
Controlled Exposure ◽  
Cellular Behaviour ◽  
Integrin Ligand

In order to study how dynamic changes of α5β1 integrin engagement affect cellular behaviour, photoactivatable derivatives of α5β1 specific ligands are presented in this article. The presence of the photoremovable protecting group (PRPG) introduced at a relevant position for integrin recognition, temporally inhibits ligand bioactivity. Light exposure at cell-compatible dose efficiently cleaves the PRPG and restores functionality. Selective cell response (attachment, spreading, migration) to the activated ligand on the surface is achieved upon controlled exposure. Spatial and temporal control of the cellular response is demonstrated, including the possibility to in situ activation. Photoactivatable integrin-selective ligands in model microenvironments will allow the study of cellular behavior in response to changes in the activation of individual integrins as consequence of dynamic variations of matrix composition.

scholarly journals Influence of Casting Solvents on CO2/CH4 Separation Using Polysulfone Membranes

Membranes ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 286
Author(s):  
Roba M. Almuhtaseb ◽  
Ahmed Awadallah-F ◽  
Shaheen A. Al-Muhtaseb ◽  
Majeda Khraisheh
Keyword(s):  
High Efficiency ◽  
In Situ Synthesis ◽  
Separation Process ◽  
Polymeric Membranes ◽  
Gas Mixture ◽  
Manufacturing Cost ◽  
Binary Gas Mixture ◽  
Maximum Permeability ◽  
Polysulfone Membranes

Polysulfone membranes exhibit resistance to high temperature with low manufacturing cost and high efficiency in the separation process. The composition of gases is an important step that estimates the efficiency of separation in membranes. As membrane types are currently becoming in demand for CO2/CH4 segregation, polysulfone will be an advantageous alternative to have in further studies. Therefore, research is undertaken in this study to evaluate two solvents: chloroform (CF) and tetrahydrofuran (THF). These solvents are tested for casting polymeric membranes from polysulfone (PSF) to separate every single component from a binary gas mixture of CO2/CH4. In addition, the effect of gas pressure was conducted from 1 to 10 bar on the behavior of the permeability and selectivity. The results refer to the fact that the maximum permeability of CO2 and CH4 for THF is 62.32 and 2.06 barrer at 1 and 2 bars, respectively. Further, the maximum permeability of CF is 57.59 and 2.12 barrer at 1 and 2 bars, respectively. The outcome selectivity values are 48 and 36 for THF and CF at 1 bar, accordingly. Furthermore, the study declares that with the increase in pressure, the permeability and selectivity values drop for CF and THF. The performance for polysulfone (PSF) membrane that is manufactured with THF is superior to that of CF relative to the Robeson upper bound. Therefore, through the results, it can be deduced that the solvent during in-situ synthesis has a significant influence on the gas separation of a binary mixture of CO2/CH4.

Comparative study of MoS2 and Co/MoS2 catalysts prepared by ex situ/in situ activation of ammonium and tetraalkylammonium thiomolybdates

2004 ◽  
Vol 210 (1-2) ◽  
pp. 105-117 ◽  
Author(s):  
L. Alvarez ◽  
J. Espino ◽  
C. Ornelas ◽  
J.L. Rico ◽  
M.T. Cortez ◽  
...  
Keyword(s):  
Comparative Study ◽  
Ex Situ ◽  
In Situ Activation ◽  
Mos2 Catalysts

Study on Mechanical Automation with Design of Rapid Milk Detector Based on Freezing Point

2013 ◽  
Vol 703 ◽  
pp. 282-286
Author(s):  
Ren Cai Zhang ◽  
Xiang Yu ◽  
Xing Ju Liu ◽  
Jin Hai Zhai ◽  
Zhen Wu Ning
Keyword(s):  
Integrated Circuit ◽  
Temperature Sensor ◽  
High Efficiency ◽  
Freezing Point ◽  
Electronic Control ◽  
Freezing Point Depression ◽  
Electronic Control System ◽  
Freezing Curve ◽  
Rack Mechanism

An efficient automated milk detector based on freezing point depression is designed. This detector shares characters of high efficiency and good stability with accuracy and automation. Its main parts include temperature sensor of IC (Integrated Circuit), pinion-rack mechanism and crank-rocker mechanism and electronic control system. Monitoring in-situ change of milk freezing curve and developing efficiency of sampling can be available by means of pinion-rack mechanism and IC temperature sensor mechatronics design. As a result, adulterating status of milk can be discriminated in a rapid and accurate and automated way. The detector may be employed to detect liquid foods other than milk as well.

Separation of phenols from oils using deep eutectic solvents and ionic liquids

2020 ◽  
Vol 92 (10) ◽  
pp. 1717-1731
Author(s):  
Yucui Hou ◽  
Zhi Feng ◽  
Jaime Ruben Sossa Cuellar ◽  
Weize Wu
Keyword(s):  
Ionic Liquids ◽  
Phenolic Compounds ◽  
High Efficiency ◽  
Deep Eutectic Solvents ◽  
Environmentally Benign ◽  
Organic Chemical ◽  
Environmental Friendliness ◽  
Oil Mixtures ◽  
Organic Chemical Industry

AbstractPhenolic compounds are important basic materials for the organic chemical industry, such as pesticides, medicines and preservatives. Phenolic compounds can be obtained from biomass, coal and petroleum via pyrolysis and liquefaction, but they are mixtures in oil. The traditional methods to separate phenols from oil using alkaline washing are not environmentally benign. To solve the problems, deep eutectic solvents (DESs) and ionic liquids (ILs) have been developed to separate phenols from oil, which shows high efficiency and environmental friendliness. In this article, we summarized the properties of DESs and ILs and the applications of DESs and ILs in the separation of phenols and oil. There are two ways in which DESs and ILs are used in these applications: (1) DESs formed in situ using different hydrogen bonding acceptors including quaternary ammonium salts, zwitterions, imidazoles and amides; (2) DESs and ILs used as extractants. The effect of water on the separation, mass transfer dynamics in the separation process, removal of neutral oil entrained in DESs, phase diagrams of phenol + oil + extractant during extraction, are also discussed. In the last, we analyze general trends for the separation and evaluate the problematic or challenging aspects in the separation of phenols from oil mixtures.

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