Physical properties of the solvent mixtures triethylphosphate+hexamethylphosphoric triamide at 25�C

Bollinger, Jean‐Claude; Yvernault, Germaine; Yvernault, Théophile

doi:10.1007/bf00644278

Cited by 25 publications

(3 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…measurements and with the new values proposed by Cataldo . It is known that TEPA 6 is not stable in acidic media, due to the catalyzed opening of the strained three‐membered cycle . It is likely that the Lewis acid catalyzes directly, or by creating other acidic species in the medium, a secondary reaction, for example polymerization, thereby biasing completely the measured enthalpy of SbCl5 addition.…”

Section: Resultsmentioning

confidence: 99%

On the Lewis Basicity of Phosphoramides: A Critical Examination of Their Donor Number through Comparison of Enthalpies of Adduct Formation with SbCl₅and BF₃

et al. 2019

View full text Add to dashboard Cite

The Lewis basicity of a series of phosphoryl compounds was examined using DFT and ab initio methods, including solvation effects. The enthalpies of adduct formation with two archetypal Lewis acids, antimony pentachloride and boron trifluoride, used to define the donor number DN and the BF3 affinity (BF3A) respectively, were examined. The BF3 adducts allow the use of the high‐accuracy G4 approach, whereas for SbCl5 adducts, three different DFT formalisms, including empirical dispersion corrections, were used because the G4 formalism is not available for third‐row elements. For a comparison with experimental data, solvation effects were taken into account by using the polarizable continuum model. The experimental BF3 affinities were well reproduced by G4 calculations when including PCM solvation. Conversely, comparisons of our calculated values and experimental results reported in the literature show that SbCl5 enthalpies for phosphoramides are in error. In particular the DN for HMPA should be revised.

show abstract

Section: Resultsmentioning

confidence: 99%

On the Lewis Basicity of Phosphoramides: A Critical Examination of Their Donor Number through Comparison of Enthalpies of Adduct Formation with SbCl₅and BF₃

et al. 2019

View full text Add to dashboard Cite

show abstract

“…Nous ne donnerons donc que des rCsultats en potentiels de demi-neutralisation dans SIB, ceux-ci variant dans le meme sens que le pK,. Les determinations dans ce mClange solvant S/B sont rapportCes aux potentiels de demi-neutralisation de la pyridine (El12 = -415 mV) et de la p-nitroaniline (El12 = -70 mV) (14).…”

Section: E ( M V )unclassified

Basicité et structure de phosphoramides aliphatiques: dosage protométrique en solvants non-aqueux

Bollinger¹,

Faure²,

Yvernault³

1983

Can. J. Chem.

View full text Add to dashboard Cite

Brönsted basicities (as half-neutralization potentials) have been determined at 25 °C by potentiometric titrations in nitromethane or in the mixture sulfolane/benzene 98:2 p/p for 19 aliphatic phosphoramides OPXYZ, with X, Y, or Z = Me; OEt; NMe2; NEt2; NHEt; N(CH2)n (n = 3 or 4); or X + Y = —NMe—(CH2)2—NMe—. Almost all of these weak bases give an homohydrogen bonding. Those with an Me or N(CH2)3 substituent are not stable in acidic medium, which is confirmed by back-titration and measure of E vs. time at the equivalent point. After comparing the results obtained in the two solvents, the effect of the nature of the substituents X, Y, Z on half-neutralization potentials and instability in acidic medium is analyzed.

show abstract

“…pGO−Co 2+ sensor response upon exposure to TEP, a representative organophosphate gas, is shown in Figure 3. In the presence of TEP, the capacitance decreased, suggesting that the water molecules, which exhibit a high dielectric constant, were substituted with TEP molecules having a lower dielectric constant, 32 (a detailed mechanistic analysis is presented below). The capacitance response time of the pGO−Co 2+ sensor upon TEP addition was ∼150 s (Figure 3A).…”

Section: ■ Experimental Sectionmentioning

confidence: 99%

Porous Graphene Oxide–Metal Ion Composite for Selective Sensing of Organophosphate Gases

2020

View full text Add to dashboard Cite

Organophosphates are used as agricultural pesticides and also encountered as toxic nerve agents in chemical warfare. Accordingly, development of sensors for detecting and monitoring organophosphate vapors is highly sought after. We present a new capacitive gas sensor exhibiting remarkable specificity and sensitivity toward the organophosphate nerve gas simulants triethyl-phosphate (TEP) and dimethyl methyl phosphate and the pesticide dichlorvos. Specifically, the capacitive sensor comprises a composite porous graphene oxide matrix intercalating cobalt or nickel ions, prepared through a simple freezedrying procedure. We demonstrate that the porous graphene oxide/ metal ion electrode undergoes fast capacitance changes only upon exposure to organophosphate vapors. Moreover, the sensor exhibits extraordinary sensitivity upon interactions with TEP. Detailed mechanistic analyses, carried out in comparison to porous graphene oxide coupled to other transition metal ions, reveal that the remarkable sensing properties of the Co 2+ or Ni 2+ /porous graphene oxide systems likely arise from the distinct mode of metal ion incorporation into the graphene oxide host matrix and substitution of metal-complexed water ligands with organophosphate molecules. The new metal ion/porous graphene oxide capacitive sensor may be employed for alerting and monitoring organophosphate gases in different environments.

show abstract

Physical properties of the solvent mixtures triethylphosphate+hexamethylphosphoric triamide at 25�C

Cited by 25 publications

References 13 publications

On the Lewis Basicity of Phosphoramides: A Critical Examination of Their Donor Number through Comparison of Enthalpies of Adduct Formation with SbCl₅and BF₃

On the Lewis Basicity of Phosphoramides: A Critical Examination of Their Donor Number through Comparison of Enthalpies of Adduct Formation with SbCl₅and BF₃

Basicité et structure de phosphoramides aliphatiques: dosage protométrique en solvants non-aqueux

Porous Graphene Oxide–Metal Ion Composite for Selective Sensing of Organophosphate Gases

Contact Info

Product

Resources

About

Physical properties of the solvent mixtures triethylphosphate+hexamethylphosphoric triamide at 25�C

Cited by 25 publications

References 13 publications

On the Lewis Basicity of Phosphoramides: A Critical Examination of Their Donor Number through Comparison of Enthalpies of Adduct Formation with SbCl5and BF3

On the Lewis Basicity of Phosphoramides: A Critical Examination of Their Donor Number through Comparison of Enthalpies of Adduct Formation with SbCl5and BF3

Basicité et structure de phosphoramides aliphatiques: dosage protométrique en solvants non-aqueux

Porous Graphene Oxide–Metal Ion Composite for Selective Sensing of Organophosphate Gases

Contact Info

Product

Resources

About

On the Lewis Basicity of Phosphoramides: A Critical Examination of Their Donor Number through Comparison of Enthalpies of Adduct Formation with SbCl₅and BF₃

On the Lewis Basicity of Phosphoramides: A Critical Examination of Their Donor Number through Comparison of Enthalpies of Adduct Formation with SbCl₅and BF₃