Solvent effects on stereochemistry of eliminations from, quaternary ammonium salts

1968 ◽  
pp. 1598
Author(s):  
David S. Bailey ◽  
William H. Saunders
Keyword(s):  
Solvent Effects ◽  
Quaternary Ammonium ◽  
Quaternary Ammonium Salts ◽  
Ammonium Salts

scholarly journals Degradation Kinetics and Solvent Effects of Various Long-Chain Quaternary Ammonium Salts

2021 ◽  
Author(s):  
Roel Kleijwegt ◽  
Wyatt Winkenwerder ◽  
Wim Baan ◽  
John van der Schaaf
Keyword(s):  
Thermal Stability ◽  
Solvent Effects ◽  
Quaternary Ammonium ◽  
Degradation Kinetics ◽  
Quaternary Ammonium Salts ◽  
Ammonium Salts ◽  
Polar Solvents ◽  
Kinetics Of ◽  
Thermal Stability Of ◽  
Long Chain

<div>Surfactants such as quaternary ammonium salts (QAS) have been in increasing demand, for emerging new applications. Recent attempts at process intensification of</div><div>their production, have disclosed the need for a better understanding of QAS thermal stability. This work aims to determine degradation kinetics of various QASs, and the</div><div>associated solvent effects. Degradation kinetics of four methyl carbonate QASs were determined in various</div><div>polar solvents in stainless steel batch autoclaves. <sup>1</sup>H NMR spectrometry was employed for online analysis of the reaction mixtures. The kinetic parameters were then used</div><div>to compare the thermal stability of the four compounds in the polar solvents. Water showed not degradation, and methanol (MeOH) was the solvent that provided the</div><div>second-best stability. Water-MeOH mixtures may provide an overall optimum. More, and longer long-chain substituents increased the degradation rate. Thermogravimetric Analysis was used to obtain the thermal stability in a solid-</div><div>state, i.e. solventless environment. Isoconversional analysis showed that no reliable kinetic parameters could be determined. Nevertheless, the data did allow for a compar-</div><div>ison of the thermal stability of 14 different QASs. Furthermore, the relative instability of the compounds in solid-state demonstrated the challenges of solventless QAS production.</div>

scholarly journals Degradation Kinetics and Solvent Effects of Various Long-Chain Quaternary Ammonium Salts

2021 ◽  
Author(s):  
Roel Kleijwegt ◽  
Wyatt Winkenwerder ◽  
Wim Baan ◽  
John van der Schaaf
Keyword(s):  
Thermal Stability ◽  
Solvent Effects ◽  
Quaternary Ammonium ◽  
Degradation Kinetics ◽  
Quaternary Ammonium Salts ◽  
Ammonium Salts ◽  
Polar Solvents ◽  
Kinetics Of ◽  
Thermal Stability Of ◽  
Long Chain

<div>Surfactants such as quaternary ammonium salts (QAS) have been in increasing demand, for emerging new applications. Recent attempts at process intensification of</div><div>their production, have disclosed the need for a better understanding of QAS thermal stability. This work aims to determine degradation kinetics of various QASs, and the</div><div>associated solvent effects. Degradation kinetics of four methyl carbonate QASs were determined in various</div><div>polar solvents in stainless steel batch autoclaves. <sup>1</sup>H NMR spectrometry was employed for online analysis of the reaction mixtures. The kinetic parameters were then used</div><div>to compare the thermal stability of the four compounds in the polar solvents. Water showed not degradation, and methanol (MeOH) was the solvent that provided the</div><div>second-best stability. Water-MeOH mixtures may provide an overall optimum. More, and longer long-chain substituents increased the degradation rate. Thermogravimetric Analysis was used to obtain the thermal stability in a solid-</div><div>state, i.e. solventless environment. Isoconversional analysis showed that no reliable kinetic parameters could be determined. Nevertheless, the data did allow for a compar-</div><div>ison of the thermal stability of 14 different QASs. Furthermore, the relative instability of the compounds in solid-state demonstrated the challenges of solventless QAS production.</div>

Synthesis and stability of 1-aminoalkylphosphonic acid quaternary ammonium salts

2021 ◽  
Author(s):  
Tomasz K. Olszewski ◽  
Anna Brol
Keyword(s):  
Phosphonic Acid ◽  
Quaternary Ammonium ◽  
Alkylating Agent ◽  
Quaternary Ammonium Salts ◽  
Ammonium Salts ◽  
Aminoalkylphosphonic Acid

An effective protocol for quaternization of simple 1-aminoalkylphosphonic acids under basic conditions and using Me2SO4 as convenient alkylating agent is reported. In the course of reaction phosphonic acid quaternary ammonium...

scholarly journals Green Accelerated Synthesis, Antimicrobial Activity and Seed Germination Test of Quaternary Ammonium Salts of 1,2-bis(4-pyridyl)ethane

Molecules ◽  
2019 ◽  
Vol 24 (13) ◽  
pp. 2424 ◽  
Author(s):  
Tăbăcaru ◽  
Botezatu ◽  
Horincar ◽  
Furdui ◽  
Dinică
Keyword(s):  
Escherichia Coli ◽  
Triticum Aestivum ◽  
Seed Germination ◽  
Quaternary Ammonium ◽  
Pathogenic Bacteria ◽  
Classical Method ◽  
Triticum Aestivum L ◽  
Quaternary Ammonium Salts ◽  
Ammonium Salts ◽  
Radicle Growth

A family of fifteen quaternary ammonium salts (QAs), bearing the 1,2-bis(4-pyridyl)ethane core, were obtained using for the first time two different green methods, such as microwave (MW) and ultrasounds (US) irradiation, with very good yields and in much shorter times compared to the classical method, and an assay on their antimicrobial action against Escherichia coli (E. coli) was carried out. While 12 to 24 hours were required for complete alkylation of 1,2-bis(4-pyridyl)ethane by reactive halogenated derivatives in anhydrous solvent under reflux conditions, MW and US irradiation reduced the reaction time and the desired products were achieved in a few min. One of the aims of this study was to evaluate the antibacterial potential of the synthesized QAs against pathogenic bacteria, along with their impact on germination activity of wheat seeds (Triticum aestivum L.). The antibacterial activity of the QAs against Escherichia coli was explored by determining the minimum inhibitory concentration (MIC). The MIC values varied from 0.312 to 2.5 mg/mL, highlighting the lowest values attained for the derivatives containing methoxy, chlorine and benzofurane functional groups. The viability of aerobic bacteria was determined with the Tetrazolium/Formazan Test, a method that was found to be the best alternative approach with respect to the difuzimetric method. Seeds of Triticum aestivum L. were used for the evaluation of the germination indicators, such as seed germination (SG), the relative seed germination (RSG), the relative radicle growth (RRG), and the seed germination index (GI). The toxicity studies of QAs 1, 4 and 7, at two different concentrations, showed no inhibitory effect on seed germination.

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