ISSN 1070-4272. Russian Journal of Applied Chemistry, 2006, Vol. 79, No. 5, pp. 791!798. + Pleiades Publishing, Inc., 2006.
Original Russian Text + O.N. Zabelina, V.E. Kirichenko, M.G. Pervova, Yu.G. Yaltuk, V.I. Saloutin, 2006, published in Zhurnal Prikladnoi Khimii, 2006,
Vol. 79, No. 5, pp. 801!808.
AND INDUSTRIAL ORGANIC CHEMISTRY
Products of the Reaction of Polychlorinated Biphenyls
with Ethanol and Potassium Hydroxide in Dimethyl Sulfoxide
O. N. Zabelina, V. E. Kirichenko, M. G. Pervova, Yu. G. Yaltuk, and V. I. Saloutin
Institute of Organic Synthesis, Ural Division, Russian Academy of Sciences, Yekaterinburg, Russia
Received October 29, 2005
Abstract-The reaction of a technical mixture of polychlorinated biphenyls with ethanol and potassium
hydroxide in dimethyl sulfoxide was studied. The composition of the products formed in the process was
determined by gas chromatography and gas chromatography!mass spectrometry.
Polychlorinated biphenyls (PCBs) are persistent
global environmental pollutants [1, 2]. The search for
methods of their safe destruction or conservation is
under way now worldwide. Also, PCBs can be proc-
essed into useful materials [2, 3]. We showed previ-
ously [4, 5] that PCBs readily react with sodium
alkoxides in polar solvents, forming a mixture of
products whose composition depends on the structure
of the alcohol and the reaction conditions. A possible
way of utilization of PCBs is to convert them to hy-
droxy and alkoxy derivatives to be further introduced
into polymer compounds.
In this study we examined reactions of congeners
of PCBs from the Sovol technical mixture with ethan-
ol and potassium hydroxide in a polar solvent and
sought for conditions ensuring the deepest conversion.
Of primary importance is identification of the reaction
products, which can be done by gas chromatography3
mass spectrometry (GC3MS) only. This study is also
of scientific importance, since nucleophilic substitu-
tion reactions in the PCB series are virtually not
The reaction mixtures were analyzed on a Shimad-
zu GC-17A gas chromatograph with a flame-ioniza-
tion detector (FID), an MDN quartz capillary column
(an analog of HP-5; length 30 m, inner diameter
0.25 mm, stationary phase film thickness 0.25 mm).
Carrier gas nitrogen, flow split ratio 1 : 30. Column
temperature: initial 100oC (1 min isotherm), pro-
grammed heating at a rate of 10 deg min
and further at a rate of 2 deg min
to 300oC. Vapor-
izer temperature 250oC; detector temperature 280oC.
The mass-spectrometric analysis was carried out on
a Fisons MD 800 instrument at the electron energy of
70 eV, scanning rate of 1 spectrum per second, re-
cording of the total ion current in the range of m/z
303400. We used an HP-5 quartz capillary column
(length 25 m, inner diameter 0.25 mm, stationary
phase film thickness 0.25 mm). Carrier gas helium,
flow split ratio 1:20. Column temperature: initial
60oC (3 min isotherm), programmed heating at a rate
of 10 deg min
to 200oC and further at a rate of
2 deg min
to 280oC. Vaporizer temperature 250oC.
We used a Sovol technical mixture comprising ca.
20% tetrachlorobiphenyls, over 50% pentachlorobi-
phenyls, ca. 20% hexachlorobiphenyls, and also minor
amounts of trichloro- and heptachlorobiphenyls. Pre-
viously , we identified the major congeners of
PCBs in the mixture, which were numbered in accor-
dance with IUPAC recommendations.
The reaction of the PCB mixture with ethanol and
KOH in dimethyl sulfoxide (DMSO) was carried out
as follows. A round-bottomed flask equipped with
a stirrer and a thermometer was charged with a solu-
tion of 5.6 g of KOH (0.1 M) in 11.5 ml (0.2 M) of
ethanol, 23 ml of DMSO, and 0.05 g of biphenyl as
internal reference. The resulting mixture was heated to
130oC until the components dissolved. Then a solu-
tion of 8.2 g (0.025 M) of the PCB mixture in 13 ml
in DMSO was added into the mixture. The tempera-
ture was raised to 150oC and kept constant for a cer-
tain period, whereupon the mixture was cooled. Then
50 ml of water, 2 ml of HCl(conc.), and 20 ml of