Electron-withdrawing substituents in meta and para positions increase whereas electron-donating substituents decrease the dissociation constants and the second-order rate constants for neutralization of l-phenyl-lnitroethanes by hydroxide ion in 50% (vol) dioxane-water. The ionization constants (PKa) and the neutralization rate constants (log kz) correlate with u constants for aqueous and for 50% (vol) dioxane-water systems. There is linear correlation of the rate constants (log k2) for neutralization and the ionization constants (pK.) of the l-phenyl-1-nitroethanes with a Brpnsted coefficient of 1.17-1.20. The Brmsted coefficient of greater than unity stems from the fact that as the electron-withdrawing capacity of the substituent is increased, the relative effects on the rate constants of neutralization of substituted 1-phenyl-1-nitroethanes are greater than on the ionization constants. meta and para electron acceptor groups accelerate and electron donor groups retard reversal of l-phenyl-l-ethanenitronates to 1-phenyl-1-nitroethanes. The Brqnsted coefficient for correlation of the logarithms of the rate constants of hydrolysis of 1-phenyl-1-ethanenitronates and thepK,'s of their 1-phenyl-1-nitroethanes is -0.17 -(-0.20).Electron-withdrawing meta and para substituents in a 1-phenyl-1-ethanenitronate result in electronic absorption at longer wavelengths. The long wavelength ultraviolet maximum of a 1-phenyl-1-ethanenitronate is shifted bathochronically in poor hydrogen bonding and in aprotic polar solvents. The rate of reversal of a l-phenyl-l-ethanenitronate upon introduction of an electron donor meta or para substituent may be retarded because the carbonitronate behaves relatively electron deficiently at CY carbon as a result of increased hydrogen bonding at oxygens of enhanced nucleophilicity and because of the increased work involved in breaking the hydrogen bonds. For salts of simple nitroalkanes there is a shift in the infrared absorption for C-N to longer wavelength as the charge density of the cation is decreased. Replacement of methyl groups for hydrogen in nitronates results in maximum ultraviolet absorption at shorter wavelengths; solvents of diminished hydrogen-bonding ability or of increased polarity lead to absorption at longer wavelengths. The effects of structure and environment on the properties of alkanenitronates are analogous to those for 1-phenyl-1-ethanenitronates. eutralization of acidic mononitro compounds is N subject to general base catalysis and there is Brdnsted correlation between the rates of neutralization of such nitro compounds and the strengths of unhindered bases.2 Previous studies of the rates of neutralization (or ionization) and the dissociation constants of nitroalkanes have been limited. The results are of interest however in that nitro compounds which are weaker (or stronger) may neutralize (or ionize) faster (slower) than their stronger (or weaker) homologs.(1) (a) (d) initial studylb of the equilibrium properties, the rate constants, and Hammett correlation for neutrali...

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The stepwise synthesis of specifically substituted trialkyl-3,4-dihydro-l (2H >naphthalenones (1-tetralones), the corresponding naphthalenes, and partially hydrogenated derivatives, several having the cadalene-type 1,4,6 substitution, has been reexamined. Individual steps have been improved and new approaches with fewer steps and higher overall yields have been devised. Syntheses utilizing lactones in Friedel-Crafts reactions were also carried out. These latter Friedel-Crafts reactions are responsible for rearrangements during tetralone syntheses which were previously attributed to polyphosphoric acid during cyclization.The synthesis of cadalene (1) became important to us as a route to pure polyalkylnaphthalenes and as a (1) E.

The methods currently reported in the literature for the characterization of nonionic surfactants are usually applied to one portion of the molecule and require a knowledge of the other portion for complete identification. This indirect approach leaves much to be desired. A simple, rapid, and more direct method of characterization is to measure the proton signal intensity in high resolution nuclear magnetic resonance (NMR) spectra. This method determines the hydrophile to hydrophobe ratio without requiring standard samples for calibration or a prior knowledge of the hydrophobe. In addition, this method will frequently give much valuable information about the identity of the hydrophobe, such as the average chain length, the degree of branching, and the type of aromatic substitution, if any. This method has been applied to the characterization of the common types of commercial polyethylene oxide condensates. The application of NMR to the analysis of formulated detergent products is also discussed.

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