Corrosion-Protecting Properties of Products of Pyridine
Quaternization with Chloromethylated Benzyltoluenes
D. A. Pisanenko, B. O. Avilov, and K. V. Likhnitskii
Kiev Polytechnic Institute, National Technical University of Ukraine, Kiev, Ukraine
Received February 9, 2010
Abstract―Substituted N-benzylpyridinium chlorides were prepared by pyridine quaternization with
chloromethylated mono-, di-, and tribenzyltoluenes. The inhibiting effect of the products on corrosion of 08kp
steel in 20% solutions of HCl at 60°С and of H
at 80°С was studied.
ISSN 1070-4272, Russian Journal of Applied Chemistry, 2010, Vol. 83, No. 9, pp. 1663–1665. © Pleiades Publishing, Ltd., 2010.
Original Russian Text © D.A. Pisanenko, B.O. Avilov, K.V. Likhnitskii, 2010, published in Zhurnal Prikladnoi Khimii, 2010, Vol. 83, No. 9, pp. 1567–1569.
We found previously  that benzyl-substituted N-
benzylpyridinium chlorides prepared by quaternization
of pyridine with chloromethylated benzylarenes
exhibit corrosion-protecting properties comparable
with those of commercial inhibitors, Katapins. Among
the compounds examined, of most interest are the salts
with the methyl group in the aryl moiety, because such
salts can be prepared from available starting sub-
stances, commercial benzyltoluenes, used as liquid
dielectrics and heat carriers [2–4]. It is known  that
corrosion-protecting properties of adsorption inhibitors
can be enhanced by using mixtures of quaternary
ammonium salts, but in  we examined the
corrosion-protecting effect only for a mixture of salts
prepared from a single composition of benzyltoluenes.
Because these salts can be effective inhibitors in
etching of ferrous and nonferrous metals , it was
interesting to examine the effect exerted on the acid
corrosion both by mixtures of such salts of various
compositions and by the individual salts. For this
purpose, we prepared salts I–VII:
Corrosion-protecting properties of the salts
obtained were studied with respect to corrosion of
08kp steel in hydrochloric and sulfuric acids. The
inhibition coefficient γ, corrosion rate K, and degree of
corrosion protection Z were determined.
Salts I–IV were synthesized by the known methods
 from benzene, toluene, diphenylmethane, and
benzyl chloride of pure grade. To prepare salts V–VII,
we used mono-, di-, and tribenzyltoluenes isolated by
fractionation of a commercial mixture of benzyl-
toluenes . Monochloromethylation of these arenes
and synthesis of pyridinium salts were performed as
described previously . The salts synthesized are
viscous liquids. Their yield based on the starting
arenes ranges from 76 to 88%. Analytical data for the
salts are consistent with their empirical formulas.
Chromatographic analysis of benzyltoluenes was
performed on a Biokhrom device (5% SE-30 on Chro-
mosorb W, carrier gas He). The amount of CH
groups introduced by chloromethylation was deter-
Н NMR spectroscopy. The
Н NMR spectra
were recorded in CCl
on a Tesla BS-487 spectrometer
(80 MHz), internal reference HMDS.
Corrosion tests were performed for 1 h by the
gravimetric procedure with samples of 08kp steel in
20% solutions of HCl and H
at 60 and 80°С,
respectively. The salts were taken in a concentration of
5 g l
counting on the anhydrous product.
R = H (I), Me (II), PhCH
(IV); n = 0 (V),
1 (VI), 2 (VII).