Closed-Shell Ion Pairs: Cation and Aggregate Dynamics of Tetraalkylammonium Salts in an Ion-Pairing Solvent (original) (raw)
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Russ. Chem. Bull., Int. Ed. 2004, 53, №8, 1711-1716
5 Methyl 4,5 dihydro 3H spiro[benzo 2 azepine 3,1´ cyclohexane] N oxide was rear ranged into 5 methyl 1 oxo 1,2,4,5 tetrahydro 3H spiro[benzo 2 azepine 3,1´ cyclohexane]. The latter was used for the synthesis of spiro{triazolo[3,4 a] and tetrazolo[5,1 a]benzo 2 azepinecyclohexanes}. Key words: spiro[benzo 2 azepinecyclohexanes], spiro{azolo[5,1 a]benzo 2 azepine cyclohexanes}, rearrangements, cyclic nitrones, fused triazoles, fused tetrazoles. 1.36 (d, 7.24-7.67 0.80-1.65 5.95 (br.s, NH) J = 11.6, J = 5.8, J = 7.0, J = 5.8, J = 7.0) J = 13.7) J = 13.7) J = 11.6) 3 1.73 (dd, 2.12 (dd, 2.97 (qdd, 1.37 (d, 7.18-7.88 0.70-1.80 8.23 (br.s, NH) J = 11.9, J = 5.8, J = 6.7, J = 5.8, J = 6.7) J = 13.7) J = 13.7) J = 11.9) 4 1.64 (m) 2.22 (m) 3.81 (m) 1.38 (d, 7.20-7.70 0.85-1.95 -J = 6.8) 5 1.74 (dd, 2.15 (dd, 2.93 (qdd, 1.27 (d, 7.15-7.40 0.65-2.00 2.45 (s, MeS) J = 11.9, J = 5.5, J = 6.7, J = 5.5, J = 6.7) J = 13.7) J = 13.7) J = 11.9) 6 2.12 (dd, 2.28 (dd, 3.11 (qdd, 1.40 (d, 7.25-7.60; 0.80-1.80 -J = 11.3, J = 5.5, J = 7.0, J = 5.5, J = 7.0) 7.95 (1 H) J = 14.0) J = 14.0) J = 11.3) 7 1.80 (dd, 2.19 (dd, 3.10 (qdd, 1.39 (d, 7.35-7.65 1.10-1.80 7.96 (BB´, J = 11.9, J = 5.5, J = 6.7, J = 5.5, J = 6.7) 3 pyridyl); J = 13.7) J = 13.7) J = 11.9) 8.66 (AA´, 2 pyridyl) 8 2.15 (dd, 2.35 (dd, 3.10 (qdd, 1.42 (d, 7.25-7.60; 0.50-1.80 7.90 (BB´, J = 11.3, J = 5.4, J = 7.0, J = 5.4, J = 7.0) 8.10 (1 H) 3 pyridyl); J = 14.2) J = 14.2) J = 11.3) 8.63 (AA´, 2 pyridyl) 9 1.86 (dd, 2.15 (dd, 3.38 (qdd, 1.39 (d, 7.23-7.64 1.00-1.80 3.96 (s, MeO) J = 11.6, J = 5.5, J = 6.7, J = 5.5, J = 6.7) J = 13.7) J = 13.7) J = 11.6) 10 1.98 (dd, 2.53 (dd, 2.96 (qdd, 1.44 (d, 7.30-7.55; 1.80-2.20; 2.28 (s, MeCO) J = 9.
J Solution Chem (2017) 46, 862–
The interaction between the amphiphilic phenothiazine drug promethazine hydrochloride (PMT) and an anionic surfactant sodium dodecylbenzenesulfonate has been investigated using the conductometric technique in the absence and presence of an inorganic salt (50 mmolÁkg -1 NaCl) at five different compositions and temperatures. PMT is employed for the cure of allergic symptoms. Different physicochemical parameters such as critical micellar concentration (cmc), thermodynamic, and micellar composition are evaluated and discussed in detail using regular solution theory (RST). The addition of salt decreased the surface charge of micelles, lowering the cmc values of the amphiphile. The interaction parameter (b) is negative at all temperatures and compositions indicating attractive interactions. Due to the presence of NaCl in mixed systems the attractive interaction (b) was further increased (b values more negative). The negative values of Gibbs energy (DG 0 m ) of mixing revealed the stability of the solution. Owing to the presence of NaCl, the DG 0 m values are found to be more negative suggesting that the driving force for interaction was significantly increased and micellization more thermodynamically favorable. Scheme 1 Molecular model of promethazine hydrochloride (PMT) J Solution Chem (2017) 46:862-885 863 1 À dm 1;c Ám 2;d m1;cm2a1þm2;dm1a2 ð5Þ m 1,c signifies constituent 1 (SDBS) dissociating into a-ions and c-ions, m 2,d denotes J Solution Chem (2017) 46:862-885 865 J Solution Chem (2017) 46:862-885 867
TTA solvation kinetics in the ionic liquid BumimTf2N
Comptes Rendus Chimie, 2007
Le comportement de la TTA, complexant généraliste des cations métalliques, a été étudié par spectroscopie UV-vis. dans le liquide ionique (LI) 1-méthyl-3-butyl-imidazolium bistriflimide (BumimTf 2 N). Selon la teneur en eau du LI, la TTA, introduite sous forme céto-hydrate, présente une cinétique d'équilibre hydrate/énol s'étalant sur plus d'une dizaine d'heures. La modélisation par une cinétique homogène classique s'avère insatisfaisante et laisse supposer l'existence de phénomènes non homogènes dans ces solutions, probablement liés à l'état de l'eau dans ce milieu.
Activity coefficients for NaBr in the system NaBr + NaFomuzte + H 2 0 at 25°C were determined from emf measurements at different lotal iomc strengths. At each total ionic strength, the measurements were carried out al different Na-FormatelNaBr ionic strength ratios. The experimental QC tivity coefficients were comparatively analyzed using Scatchard's, Pitzer' s and Lim's methods. Allhough all these models can be successfully applied to the anaJysis of Ihis mixed syslem, Ihe All Mixing CoefflCients (LA) and Consislency Test (LT) models lead lo better fittings lhan lhe olhers.
Journal of the American Chemical Society, 1974
The approach to equilibrium and the values of the equilibrium constant were investigated in the reaction system (kr) t-C4Hs' + i-CSH1? i-C5H11T + i-C I H I~ (k,) by pulsed high-pressure mass spectrometry. The equilibrium constants measured and the resultant thermodynamic values, AH =-3.3 kcal/mol, AGaO0 =-2.5 kcal/ mol, ASzoo =-2.7 eu, showed good agreement with values obtained previously using a continuous ion source technique. The value of ki was measured as 1.6 X IO-" cm3/(mol sec) at 328°K. The rate constant for this slow exothermic bimolecular reaction exhibits a temperature dependence between 190 and 570°K best expressed as kr = CT-3. The meaning of this temperature dependence in the present reaction system, involving a highly complex reaction intermediate with 3N-6 = 84 internal degrees of freedom, is discussed in the context of transition state theory concepts. he thermodynamics of the hydride-transfer equi
J Chem Eng Data, 1990
Dendtles for ternary solutions In the system NaCI-CaCI,-H,O were measured wlth a vlbratlng-tube dencrlmeter at 298.15 f 0.09 and 308.15 f 0.03 K and 0.1 MPa and over a range of Ionic strengths from 0.1 to 19.2 mol-kg-'. The present results are In excellent agreement wHh previously published data for the NaCI-H,O bhary and are in very good agreement wlth the more precise of the available data for the CaCI,-H,O blnary at 298.15 K. Very large dlscrepancles between the results of the three most recent reports of dendtles for the CaCI,-H,O system at 308.15 K are resolved here, Improving both the accuracy and preclslon for this system. Most slgnlfkantty, the results reported here substantially expand the vohmetrlc data base for ternary solutlons. On the bad8 of the results of this study, most of the previously reported 308.15 K dendty data In the ternary system appear to contain large errors. We have evaluated the data wlthln the framework of the Pltzer formaltam and obtain new values for the Ion Interaction and mlxlng parameters for this ternary system. In addltlon to the parameters determlned from the blnary end-member solutions, It was found that only BG,c, was needed to represent the ternary results.
Effet de contre-ion sur les propriétés d'amphiphiles cationiques
2007
Des tensioactifs dimeriques cationiques ont ete etudies en faisant varier la nature du contre-ion afin de determiner quels sont les effets ioniques qui influencent principalement leurs proprietes d'agregation. La methode de synthese de ces molecules a ete adaptee afin de permettre l'investigation d'une large variete de systemes se distinguant par leur contre-ion. La micellisation de ces tensioactifs a fait l'objet d'une etude par conductimetrie qui a permis de montrer l'influence preponderante de l'hydrophobie du contre-ion associee a des effets secondaires tels que l'hydratation ou la morphologie du contre-ion. Nous avons aussi montre comment l'utilisation d'un colorant, l'Orange de Methyle, peut s'averer etre un outil d'investigation de l'hydratation et de l'ionisation des micelles. La solubilite de ces tensioactifs dans l'eau a egalement ete examinee a travers l'etude de leur temperature de Krafft en fonction du ...
2003_Coord_Chem_29_1_PredictKStabil.pdf
Regression analysis was used to derive equations for estimaing thermodynamic stability constants for complexes of Cr 2+ ( [Cr 2+ L] = 0.53 [H n L]) and Cr 3+ ( [Cr 3+ L] = 0.88 [H n L]) from