Unusual reaction of hexaethylphosphorous triamide with mercuric chloride leading to the formation of metallic mercury

Full text of DOI:10.1023/A:1015007123845

Russian Chemical Bulletin, International Edition, Vol. 51, No. 1, p. 191, January, 2002
191
Letters to the Editor
Unusual reaction of hexaethylphosphorous triamide with mercuric chloride
leading to the formation of metallic mercury
Yu. G. Gololobov, E. M. Ivanova, and P. V. Petrovskii
A. N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences,
2
8 ul. Vavilova, 119991 Moscow, Russian Federation.
Fax: +7 (095) 135 5085. Eꢀmail: yugol@ineos.ac.ru
As a rule, trivalent phosphorus compounds form stable
adducts with metal salts. For example, a stable complex
of mercuric chloride with triisopropylphosphine is known
thick grayꢀgreen mass with mercury drops, and the mixture was
filtered. The filtrate was concentrated in vacuo to dryness. The
total weight of the combined dry residue and precipitate conꢀ
taining metallic mercury was 2.33 g. The mercury was washed
with CH Cl ; the yield of metallic mercury was 0.79 g (98%).
1
31
(
P NMR (CDCl ), δ : 78.49, J199
31 = 6966 Hz*).
3
P
Hg— P
2
2
However, we found that a complex of mercuric chloꢀ
The 3 P NMR spectrum recorded in CH Cl shows two sets of
1
2
2
ride with hexaethylphosphorous triamide, which is readily
formed in dry acetonitrile, gradually decomposes in air to
give metallic mercury in quantitative yield. The reaction
mixture contains diethylamine hydrochloride and a mixꢀ
ture of phosphorus compounds with chemical shifts charꢀ
acteristic of pyrophosphates. Apparently, this process inꢀ
volves atmospheric moisture:
signals at δ –10 to –12 and –23 to –26 ppm, including a singlet
P
at δP –11.61 (24%) and doublets and triplets with JP—P
=
21—22 Hz. Apparently, these are diethylammonium acid diꢀ
and triphosphates. Methylene dichloride was evaporated, and
the powder (1.5 g) was crystallized from methylene dichloride—
ether. The yield of colorless crystals was 0.4 g, m.p. 226—227 °C.
1
The H NMR spectrum is identical with that of diethylamine
hydrochloride.
(
Et N) P + HgCl + 4 H O
This transformation is probably the first example of
the reduction of metal chlorides with amides of P acids
in the presence of moisture.
2
3
2
2
III
Hg + 2 Et NH•HCl +
2
+
(a mixture of phosphorusꢀcontaining compounds).
References
Hexaethylphosphorous triamide (1.1 g, 0.0049 mol) was
added dropwise to a solution of mercuric chloride (1.1 g,
1
. Yu. G. Gololobov, M. A. Galkina, O. V. Dovgan´, I. Yu.
Krasnova, P. V. Petrovskii, M. Yu. Antipin, I. I. Vorontsov,
K. A. Lysenko, and R. Schmutzler, Izv. Akad. Nauk, Ser.
Khim., 2001, 269 [Russ. Chem. Bull., Int. Ed., 2001, 50, 279].
0
.004 mol) in dry acetonitrile (2 mL). This is a slightly exotherꢀ
31
mic reaction. According to the P NMR data, the reaction
mixture contains a phosphorus compound with δP 110.75,
J
199Hg—31P = 11540 Hz. The reaction mixture was left in an open
vessel at ∼ 20 °C. After 10 days, ether (20 mL) was added to a
Received August 30, 2001;
*
J
199
31 in Ref. 1 is not correct.
in revised form November 16, 2001
Hg—
P
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, p. 179, January, 2002.
066ꢀ5285/02/5101ꢀ191 $27.00 © 2002 Plenum Publishing Corporation
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