Anticorrosion Properties of 8-Oxyquinoline Derivatives

For the development of new complex inhibitors of acid corrosion in steels within the framework of the QSPR approach, we study the anticorrosion properties of the samples of arylsulfonyl esters of 8-oxyquinoline in sulfuric acid and compare their electronic characteristics with the data of quantumchemical analysis in the РМ7 semiempirical approximation. The following series of esters were investigated: naphthalene-1-yl-benzosulfonate (1), 4-methylbenzosulfonate (2), 4-nitrobenzosulfonate (3), 2-methylbenzosulfonate (4), naphthalene-1-sulfonate (5) and, for the sake of comparison, the original compound, i.e., 8-oxyquinoline (0). Samples of 20 steel were tested in a model corrosive medium by the gravimetric method under the following conditions: 0.1 М solution of sulfuric acid, a temperature of the medium equal to 55°С, the duration of experiment equal to 2.5 h (in the vibration mode), and a concentration of sulfonyl esters of 0.01 mole/liter. We obtain the following sequence of increase in the anticorrosion activity of these compounds: (0)