DICHLOROPHOSPHATE ANION IN THE SYNTHESIS OF THIOAMIDES
1021
mixture obtained was left for 16 h at room tempera-
ture to complete transformation of PSCl3 into dichlo-
according to the procedure a. Reaction duration
45 days, bp 105 106 C (12 mm), yield 41%.
rothiophosphate anion. The 31P NMR spectrum
,
P
b. Dimethylthioacetamide VIII was obtained
analogously to dimethylthioformamide according to
the procedure b from triethylammoniun dichlorothio-
phosphate IV. Reaction completed in 16 h, yield 93%.
43 ppm. The obtained solution of anion X in chloro-
form was treated with 2.1 g of DMF at 20 C with the
protection of reaction mixture from air moisture.
Resulting mixture was stirred for 4 h until the disap-
pearance of a signal related to dichlorothiophosphate
anion from the 31P NMR spectrum. The reaction
mixture was diluted with 50 ml of water and dime-
thylthioformamide was extracted with 30 ml of chloro-
form. The extract obtained was dried over sodium
sulfate, solvent was removed at reduced pressure, an
the product was distilled in a vacuum. Yield 91%.
2,3,5,6-Tetramethyl-4-thia-2,6-diaza-2,5-hexa-
diene dichlorophosphate chloride (VII) was pre-
1
pared analogously to the product V. H NMR spec-
trum, , ppm: 2.54 s (3H, CH3); 3.24 s [6H, (CH3)2N].
31P NMR spectrum, P, ppm: 4.9 s. Hydrolysis of
salt VII gave dimethylthioacetamide in 43% yield.
REFERENCES
2,6-Dimethyl-4-thia-2,6-diaza-2,5-hexadiene
dichlorophosphate chloride (V). a. PSCl3, 5 g, and
4.2 g of anhydrous DMF were dissolved in 30 ml of
anhydrous chloroform and kept at 20 C to complete
disappearance of PSCl3 signal (34.9 ppm) from 31P
NMR spectrum. The reaction has completed in 5 days.
Solvent was removed in a vacuum, the crystalline
residue was washed with diethyl ether and dried under
1. Metzger, J.V., Comprehensive Heterocyclic Che-
mistry, Katritzky, A.R. and Rees, C.W., Eds., Oxford:
Pergamon Press, 1984, vol. 6, pp. 235, 294.
2. Franz, J.E. and Dhingra, O.P., Comprehensive Hete-
rocyclic Chemistry, Katritzky, A.R. and Rees, C.W.,
Eds., Oxford: Pergamon Press, 1984, vol 6, pp. 463,
492.
an oil pump vacuun. Yield of the salt V 6.0 g (97%).
1
31P NMR spectrum,
,
5.0 ppm. H NMR spect-
3. Hurd, R.N. and De La Mater, G., Chem. Rev., 1961,
P
vol. 61, no. 1, p. 45.
rum, , ppm: 3.29 s [6H, (CH3)2N], 8.26 s (1H, CH).
Found, %: C 22.11; H 4.12; Cl 33.70; N 8.67; P
10.41; S 9.97. C6H14Cl3N2O2PS. Calculated, %: C
22.83; H 4.47; Cl 33.70; N 8.87; P 9.81; S 10.16.
4. Kuliev, A.B., Abdullaeva, M.I., and Akhadov, N.O.,
Zh. Prikl. Khim., 1984, vol. 57, no. 8, p. 1835.
5. Scheibyl, S., Pedersen, B.S., and Lawesson, S.-O.,
Bull. Soc. chim. Belg., 1978, vol. 87, no. 3, p. 229.
b. A solution of 2.1 g of phosphorus oxychloride
and 1 g of DMF in 15 ml of anhydrous chloroform
was kept at 20 C for 16 h to complete conversion of
POCl3 to dichlorophosphate anion, 31P NMR spec-
trum, P, 6.1 ppm. The solution obtained was treated
with 1.2 g of dimethylthioformamide. After 1 h for-
mation of salt V was registered. The salt was isolated
as described in the procedure a. Yield of the salt V
4.1 g (96%). The constants of the compounds ob-
tained by both the methods are identical.
6. Yde, B., Yousif, N.M., Pedersen, B.S., Thomsen, J.,
and Lawesson, S.-O., Tetrahedron, 1984, vol. 40,
no. 11, p. 2047.
7. Cherkasov, R.A., Kutyrev, G.A., and Pudovik, A.N.,
Tetrahedron, 1985, vol. 41, no. 13, p. 2567.
8. Bodine, J.J. and Kaloustian, M.K., Synth. Commun.,
1982, vol. 12, no. 10, p. 787.
9. Ishii, Y., Hirabayashi, T., and Imaeda, H., Japan
Patent no. 40441, 1974; C.A., 1975, vol. 82, 156074f.
Hydrolysis of compound (V). Water, 30 ml, was
added dropwise with stirring and cooling with ice
water to 5 g of the dry salt V. Dimethylthioformamide
formed was extracted with chloroform, the extract
obtained was dried over sodium sulfate, solvent was
removed in a vacuum, and the residue was distilled
in a vacuum. Yield of dimethylthioformamide 42%.
10. Ilankumaran, P., Ramesha, A.R., and Chandraseka-
ran, S., Tetrahedron Lett., 1995, vol. 36, no. 4,
p. 8311.
11. Pedersen, B.S. and Lawesson, S.-O., Bull Soc. Chim.
Belg., 1977, vol. 86, no. 9, p. 693.
12. Brillon, D., Synth. Commun., 1990, vol. 20, no. 19,
p. 3085.
Dimethylthioacetamide (VIII). a. Dimethylthio-
acetamide VIII was obtained analogously to dimethyl-
thioformamide from PSCl3 and dimethylacetamide
13. Kanthehner, W., Haug, E., and Farkas, M., Lieb. Ann.,
1982, vol. 1982, no. 8, p. 1582.
RUSSIAN JOURNAL OF GENERAL CHEMISTRY Vol. 76 No. 7 2006