Acidity of benzene

Experimental and theoretical studies of the basicity and acidity of benzene-substituted indoles were performed169. In aqueous solution, the pK values are above —4 for the bases and above 15 for the acids. Gas-phase ionization enthalpies have been calculated using the AMI semiempirical method. 

X-ray dipole moments of formamide, of sulfamic acid, of benzene chromium tricarbonyl, and of water, obtained from /c-refinements, are in good agreement with those from other physical techniques. When hydrogen-atom positions are of crucial importance, as in the case of the water molecule, the availability of positional information from neutron diffraction becomes essential if accurate moments are to be obtained. In other cases, extension of the X-H bond to accepted values provides a reasonable alternative. 

In 1910, only four years after being appointed as Lecturer, Boyle received her D.Sc., the subject of her research being the iodosulphonic acids of benzene. One of her obituaries noted ... 

The para or 1-4-di-sulphonic acid of benzene is also known and likewise the 1-3-5-tri-sulphonic acid. 

Sulphonic Acids of Benzene Homologues.—The homologues of benzene react in the same way toward sulphuric acid with the difference, already mentioned, that substitution takes place even more easily, due to the presence in the ring of methyl or other aliphatic radicals. Toluene sulphonic acids are, therefore, more easily prepared than benzene sulphonic acid. 

The known acidities of benzene and methane are nsed as standards for the others. 

The acidity of benzene, toluene, xylenes, naphthas, and other aromatic hydrocarbons is determined by the titration of a water extract with 0.01 N sodium hydroxide in the presence of 0.5% phenolphthalein indicator solution. The method is suitable for setting specifications, internal quality control, and development of solvents. The result indicates the potential corrosivity of solvent. 

ASTM D 847-96. Standard test method for acidity of benzene, toluene, xylenes, solvent naphthas, and... 

The name of the carboxylic acid of benzene is benzoic acid. The carbon of the carboxyl group is bonded to carbon 1 in the ring, and the ring is numbered to give the lowest numbers for any substituents. 

D847 Acidity of Benzene, Toluene, Xylenes, Solvent Naph-... 

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