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Solvents and effects

Reichardt C 1988 Solvents and Solvent Effects in Organic Ohemistry (Weinheim VCH)... [Pg.864]

A3.8.4 QUANTUM ACTIVATED RATE PROCESSES AND SOLVENT EFFECTS... [Pg.891]

Cacace M G, Landau E M and Ramsden J J 1997 The Hofmeister series salt and solvent effects on interfacial phenomena Q. Rev. Biophys. 30 241-78... [Pg.2847]

YETI is a force held designed for the accurate representation of nonbonded interactions. It is most often used for modeling interactions between biomolecules and small substrate molecules. It is not designed for molecular geometry optimization so researchers often optimize the molecular geometry with some other force held, such as AMBER, then use YETI to model the docking process. Recent additions to YETI are support for metals and solvent effects. [Pg.56]

Vinylogous shift of about 100 run in symmetrical dyes, convergent and nonconvergent series, and solvent effects, have also been successfully interpreted by Brooker s and Kiprianov s conceptions. [Pg.70]

The subscript 0 on 1 implies 0 conditions, a state of affairs characterized in Chap. 1 by the compensation of chain-excluded volume and solvent effects on coil dimensions. In the present context we are applying this result to bulk polymer with no solvent present. We shall see in Chap. 9, however, that coil dimensions in bulk polymers and in solutions under 0 conditions are the same. [Pg.112]

A theoretical, comparative study of the tautomerism of 56 five-membered heterocyclic rings announced in (76AHC(Sl)l) has appeared (81MI40402). The stabilities of the three forms for 5-pyrazolones, 5-pyrazolethiones and 5-aminopyrazoles have been calculated by a simple Hiickel o) iterative method. The relative energies and the substituent and solvent effects are in agreement with the experimental results. [Pg.215]

A prototype of such phenomena can be seen in even the simplest carboxylic acid, acetic acid (CH3CHOOH). Acidity is determined by the energy or free energy difference between the dissociated and nondissociated forms, whose energetics usually depend significantly on their conformation, e.g., the syn/anti conformational change of the carboxyl-ate group in the compound substantially affects the acid-base equilibrium. The coupled conformation and solvent effects on acidity is treated in Ref. 20. [Pg.427]

In this section, we review three studies on the coupled substimtion and solvent effects on basicity and acidity. [Pg.428]

For a broad review of substituent and solvent effects on acidity and basicity, see R. W. Taft, Prog. Phys. Org. Chem. 14 247 (1983). [Pg.247]

The followmg types of studies will not be presented individually but may have contnbuted supportmg data to coverage by compound type conformational analyses [23 24, 25, 26 27], fluoropolymers [28, 29, 30 31, 32], solid-state NMR [ii], and solvent effects [34 35, 36, 37] Many excellent articles with m-depth NMR interpretation of one specific compound or of a small, structurally related group of compounds can be found in the chemical hterature A few of these, not incorporated elsewhere in this secUon are referenced here carbonyl fluondes [JS 39 40], fluoropropanes [41 42, 43], fluorocyclopropanes [44, 45 46], fluorobutanes [47], perfluorocyclobutanone [48], fluorohexanes [49], and vinyl fluondes [50, 51 52, 53, 54]... [Pg.1039]

After an introductory chapter, phenomenological kinetics is treated in Chapters 2, 3, and 4. The theory of chemical kinetics, in the form most applicable to solution studies, is described in Chapter 5 and is used in subsequent chapters. The treatments of mechanistic interpretations of the transition state theory, structure-reactivity relationships, and solvent effects are more extensive than is usual in an introductory textbook. The book could serve as the basis of a one-semester course, and I hope that it also may be found useful for self-instruction. [Pg.487]

The reactions of enamines as 1,3-dipolarophiles provide the most extensive examples of applications to heterocyclic syntheses. Thus the addition of aryl azides to a large number of cyclic (596-598) and acyclic (599-602) enamines has led to aminotriazolines which could be converted to triazoles with acid. Particular attention has been given to the direction of azide addition (601,603). While the observed products suggest a transition state in which the development of charges gives greater directional control than steric factors, kinetic data and solvent effects (604-606) speak against zwitterionic intermediates and support the usual 1,3-dipolar addition mechanism. [Pg.440]

Solutiffin Here are the predicted energy differences and solvent effects in the four solvent environments ... [Pg.242]

The study on ring transformations of heterocycles is an attractive subject of research for many years. This great interest is due to the fact that these reactions are usually easily performed and that by these ring transformations heterocycles can be synthesized which are otherwise difficult to obtain. Moreover, unravelling the course of the ring transformation has always been a challenging problem and has attracted the interest of many chemists it requires studies on substituent and solvent effects, labeling and NMR studies, kinetic studies and quantum chemical calculations. In the course of... [Pg.31]

Figure 11.7 Energy diagrams showing the effects of (a) substrate, (b) nucleophile, (c) leaving group, and (d) solvent on Sn2 reaction rates. Substrate and leaving group effects are felt primarily in the transition state. Nucleophile and solvent effects are felt primarily in the reactant ground state. Figure 11.7 Energy diagrams showing the effects of (a) substrate, (b) nucleophile, (c) leaving group, and (d) solvent on Sn2 reaction rates. Substrate and leaving group effects are felt primarily in the transition state. Nucleophile and solvent effects are felt primarily in the reactant ground state.
The pH will depend upon the ionic strength of the solution (which is, of course, related to the activity coefficient — see Section 2.5). Hence, when making a colour comparison for the determination of the pH of a solution, not only must the indicator concentration be the same in the two solutions but the ionic strength must also be equal or approximately equal. The equation incidentally provides an explanation of the so-called salt and solvent effects which are observed with indicators. The colour-change equilibrium at any particular ionic strength (constant activity-coefficient term) can be expressed by a condensed form of equation (4) ... [Pg.264]

C. Reichardt, Solvent and Solvent Effects in Organic Chemistry, 2nd. ed., VCH, Wein-heim, 1988. [Pg.492]

The evidence presented so far excludes the formation of dissociated ions as the principal precursor to sulfone, since such a mechanism would yield a mixture of two isomeric sulfones. Similarly, in the case of optically active ester a racemic product should be formed. The observed data are consistent with either an ion-pair mechanism or a more concerted cyclic intramolecular mechanism involving little change between the polarity of the ground state and transition state. Support for the second alternative was found from measurements of the substituent and solvent effects on the rate of reaction. [Pg.671]

Kamlet MJ, Abboud J-LM, Taft RW (1981) Prog Phys Org Chem 13 485 Reichardt C (2003) Solvents and Solvent Effects in Organic Chemistry, 3rd edn. VCH, Weinheim, p 389... [Pg.145]

Jung M. E. Substituent and Solvent Effects in Intramolecular Diels-Alder Reactions Synlett 1990 186-190... [Pg.324]


See other pages where Solvents and effects is mentioned: [Pg.888]    [Pg.613]    [Pg.228]    [Pg.173]    [Pg.290]    [Pg.293]    [Pg.285]    [Pg.285]    [Pg.301]    [Pg.314]    [Pg.11]    [Pg.217]    [Pg.443]    [Pg.421]    [Pg.674]    [Pg.723]    [Pg.600]   
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See also in sourсe #XX -- [ Pg.170 , Pg.764 ]

See also in sourсe #XX -- [ Pg.430 ]




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And solvent isotope effects

Aqueous Solvent Equilibrium and Kinetic Isotope Effects

EFFECT OF SOLVENT ON CHEMICAL REACTIONS AND REACTIVITY

ELECTRONIC AND ELECTRICAL EFFECTS OF SOLVENTS

Effect of Sensitizers and Solvents on Chemoselectivity

Effect of Solvent and Counterion

Effect of resins, solvents, and additives on aggregation

Effect of solvent and radical traps

Effect of solvent and temperature on intrinsic viscosity

Effect of solvents and additives

Effects of Additives, Solvents, and Impurities

Effects of Solvent and Block Copolymer Composition

Effects of Solvent and Concentration on Periselectivity

Effects of Solvent and Temperature

Effects of Solvent, Leaving Group, and Nucleophile on Unimolecular Substitution

Effects of Solvents, Surfactants, and Complexing Agents on Stability

Effects of pH and Solvent

Effects of solvent-concentration, adsorption temperature and pressure

Effects on health of solvents from paints and varnishes

Electron-directing and steric effects solvents

Empirical and Semiempirical Treatments of Solvent Effects

Equilibrium Constants, Temperature, and Solvent Effects

Excluded Volume and Solvent Effects

External Pressure and Solvent Effects on Reaction Rates

Heteroatom, Substituent, and Solvent Effects

Hydrogen bonding and solvent effects

Hydrogen bonding and solvent effects on rate of nucleophilic

Hydrogen bonds and solvent effects in soil

Hydrogen bonds and solvent effects in soil processes

Inductive and solvent effects

Limiting Unimolecular Nucleophilic Reactions—Effects of Structure and Solvent

Mutual Effects of Ions and Solvents

Nucleophilicity and Solvent Effects

PPV Polymers and Solvent Effect

Protic and Dipolar Aprotic Solvent Effects on the Rates of Sn Reactions

Reagent and Solvent Effects

Separation of Initial and Transition State Solvent Effects

Sn2 reaction solvent effects and

Solvation and solvent effects

Solvent Effect and Aromatic Compounds Magneto-Optic Properties

Solvent Effects and Reaction Intermediate

Solvent Effects in Chemistry, Second Edition. Erwin Buncel and Robert A. Stairs

Solvent Effects in Competitive Homolytic and Heterolytic Dediazoniation

Solvent Effects on Acidity and Basicity from Gas Phase Ion Equilibria Measurements

Solvent Effects on Enolate Structure and Reactivity

Solvent Effects on Mechanisms and Stereochemistry of Organic Reactions

Solvent Effects on ORD and CD Spectra

Solvent Effects on Polar and Ionic Reactions

Solvent and Additive Effects on Olefin Metathesis

Solvent and Substituent Effects

Solvent and pH Effects

Solvent and pressure effect

Solvent and temperature effect

Solvent effect on chain dimensions and conformations of polysaccharides

Solvent effect on charged polysaccharides and the polyelectrolyte model

Solvent effects and chemical reactivity

Solvent effects and rate of nucleophilic

Solvent effects and rate of nucleophilic substitution

Solvent effects, and rate

Solvent effects, reaction coordinates, and

Solvent effects, reaction coordinates, and reorganization energies

Solvent effects, reaction coordinates, and reorganization energies on nucleophilic substitution

Solvent effects, reaction coordinates, and reorganization energies on nucleophilic substitution reactions in aqueous solution

Solvent medium effects and excess polarizabilities

Solvents and Solvent Effects in Organic Chemistry, Third Edition. Christian Reichardt

Steric and Solvent Effects in Substitution

Structural and Solvent Effects in SN Reactions

Studies of Equilibria, Reactions, and Solvent Effects

Studies of Equilibria, Shift Reagents, and Solvent Effects

Substituent, Solvent and Isotope Effects

Swelling and Solvent Effects

Temperature Dependence and Solvent Effects

The Combined Effect of Temperature and Solvent Composition on Solute Retention

The Solvent Effect and Mechanism

The Solvent and its Effect on Reactions in Solution

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