Grunwald-Winstein plots

Equation (50) correlates rate constants for a number of solvolysis reactions and Figure 13 illustrates the Grunwald-Winstein plot for the solvolysis of z-butyl chloride against a K value from 1-adamantyl chloride where w = 0.78. 

Construct a Grunwald-Winstein plot and comment briefly on the magnitude of the slope. The y, Ad parameter is determined from the solvolysis of 1 -adamantyl chloride. 

Figure 11 Extended Grunwald-Winstein plot for the solvolysis of isopropyl tosylate , plot of the data against , improved plot when bilinear equation is...

Figure 1. Grunwald-Winstein plot for the solvolysis of the t-BuSMe2+ ion. The line represents the best fit to the data of reference 23 (excluding acetolysis). The points represent our data for the solvolysis of t-BuSMe OTf- at 50.0 °C.

Kinetic studies of the solvolysis of phenylmethanesulfonyl chloride (PhCH2S02Cl) in a wide range of solvent mixtures at 308 K were reported. Since an extended Grunwald-Winstein plot was linear and a kinetic solvent isotope effect of 2.34 was seen for MeOH/MeOD, a dissociative S 2 mechanism was indicated. ... 

Explain why the relief of ring strain or steric strain in an SnI reaction can often lead to small m values (reaction constants in Grunwald-Winstein plots). 

Univariate LSERs may possess the conventional LEER form, as exemplified by Eq. (8-67), the Grunwald-Winstein equation, or they may simply be plots of log k against a solvent parameter such as Z, (30), or ir. Brownstein developed an LEER form for the latter type of correlation, writing... 

A dissociative mechanism is proposed for the aquation of // a -[Cr(en)2Cl2] ion from studies in aqueous-organic solvent mixtures (0—50% MeOH, ethylene glycol, glycerol, acetone, and dioxan). Plots of In A with e ( = dielectric constant of solvent) or the Grunwald-Winstein T-values are linear, and comparison with the analogous Co systems indicates far less charge separation in the transition state. 

Examples of Grunwald-Winstein treatments of reactivity trends have become rare in inorganic chemistry. Some more information has been presented on such plots for aquation of [M(NH3)5Br] + cations with M=Cr or Co in aqueous alcohols. The variation of rate constant with solvent Y value for the isomerization of a chlorophenylacetylene complex of platinum to its chloro-phenylalkynyl form, equation (3), is so small that an intramolecular mechanism is indicated. ... 

The cr-substituent effects and solvent effects (extended Grunwald-Winstein equation) for solvolyses of / -X-substituted benzoyl chlorides (X = OMe, Me, H, and Cl) in 97% wt/wt hexafluoroisopropanol/water was explained by two competing pathways. Plots of log k versus a were consistent with a cationic path and explained by an 5 n2-5n1 spectrum of mechanism. Electron-donating groups favoured the reaction and values of p increased in the order AcOH < HCO2H < TEE < HFIP. A benzoyl cation intermediate was trapped in hexafluoroisopropanol. Ab initio calculations of heterolytic bond dissociation energies of various chloro- and fluoro-substituted and other benzoyl chlorides were correlated with log k for solvolyses... 

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