Showing papers in "Journal of the American Chemical Society in 1963"
TL;DR: In this paper, the rate data for the generalized nucleophilic displacement reaction were reviewed, and the authors presented a method to estimate the rate of the generalized displacement reaction in terms of the number of nucleophiles.
Abstract: Recently (1) the rate data for the generalized nucleophilic displacement reaction were reviewed.
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TL;DR: In this article, the oxidation half-wave potentials of fifty-three organic compounds were determined in acetonitrile at a rotating Pt electrode, and these values were correlated with ionization potentials, with interaction energies of charge transfer complexes with trinitrofluorenone, with Huckel coefficients of the resonance integral in the expression for the highest occupied molecular orbital energy level, and with pabsorption band spectra.
Abstract: The oxidation half-wave potentials of fifty-three organic compounds were determined in acetonitrile at a rotating Pt electrode. These values are correlated with ionization potentials, with interaction energies of charge- transfer complexes with trinitrofluorenone, with Huckel coefficients of the resonance integral in the expression for the highest occupied molecular orbital energy level, and with pabsorption band spectra. The correlations yield linear relations for alternate hydrocarbons. On the basis of these correlations, the values of the oxidation half-wave potentials are applied to calculate ionization potentials for aromatic hydrocarbons and to verify the values of molecular orbital calculations. (auth)
TL;DR: In this paper, the F-19 NMR shielding parameters for 21 meta substituted fluorobenzenes relative to a fixed external standard and relative to fluorobenzene as an internal standard were obtained at room temperature at high dilution in 20 widely varying pure solvents.
Abstract: : The F-19 NMR shielding parameters for 21 meta substituted fluorobenzenes relative to a fixed external standard and relative to fluorobenzene as an internal standard were obtained at room temperature at high dilution in 20 widely varying pure solvents. Extensive measurements with 24 additional substituent groups in non-polar and in hydroxylic solvents, both pure and mixed, wereALSO MADE. In spite of a variation over 9.2 ppm in shielding for a given fluorobenzene relative to the fixed external standard, the shielding parameters for seven compounds with chemically inert meta substituents relative to internal fluorobenzene are solvent invariant to a precision of the same order as experimental error. This result offers critical evidence that intermolecular shielding resulting from interaction of the F atom with solvent makes little or no contribution to the shielding parameter of a meta substituted fluorobenzene relative to fluorobenzene as the internal standard. A further conclusion is that the field effect makes no practical contribution to the variation in shielding due to meta (and presumably para) substituents. It is further implied that the bond dipole moments of groups are independent to good precision of this variation in dielectric constant for many nonprotonic solvents at room temperatures. The effects of solvent on the shielding parameter of meta substituted fluorobenzenes with chemically active substituents is attributed to charge-transfer solvent-substituent interactions. (Author)
TL;DR: Ultraviolet spectrum in methanol: 6~-Nitro-3~,5~-cycloandrostan-17-one (XVII)29 (Fig. 16): C.R.D. in methangl ( c 0.0474, 280 -240 mp): [+I311 -7950 , [+]305 -8030 , +P500).
Abstract: [8JR40 0, O.R.D. in methangl ( c 0.948, 41: 280 \"1.1; c 0.0474, 280 -240 mp): [+I311 -7950 , [+]305 -8030 , +P500\". Ultraviolet spectrum in methanol: ATE e 97. 66-Nitrotestosterone acetate (XVI)26 (Fig. 16): C.D. in methanol ( c 0.775, 400-330 mp; c 0.086, 330-275 mp; c 0.0215, 275-260 mp; c 0.01075, 260-240 mp): [8]400 0, +240, [8]s j i 0, [91?sl -16200, 0, [ 8 ] ~ ~ f l5100 . O .R .D. in methanol ( c 0235,400-290 mp; c 0.0147,290-230 mp) : [+ ]ao? -6560\". Ultraviolet spectrum in methanol: 6~-Nitro-3~,5~-cycloandrostan-17-one (XVII)29 (Fig. 17): C .D . in methanol ( e 0.708, 350-240 mp): I81330 0, [ 6 ] 3 ? 6 4-540, [ 8 ] 3 2 1 0, 1813133 f 3 1 2 0 , [8)?ss0, [8]2i3 -2160, [ 8 ] 2 ~ 0 , [ 8 ] m +780. oO.R.D. in methanol ( c 0.0804, 350-235 mp) : [ @ I d 1 6 +1900 , [ + ] 2 s i -3240\", [@I?,; + 1080\". Ultraviolet spectrum in methanol: Aya; log e 2.11. 1100, [ 8 ] a 4 0 .