Molecules 2001, 6, M233

Bis[(3,5-dimethyl pyrazol)-1-yl Thiocarbonyl)] Disulfide

Abderrahman El Idrissi, Karim Tebbji and Smaail Radi

Laboratoire de Chimie Organique Physique, Faculté des Sciences-oujda, Morocco
Fax: +212 56 50 06 03. E-mail: [email protected]

Received: 22 February 2001 / Accepted: 15 May 2001 / Published: 25 May 2001

This experiment is performed according to literature method [1-4]. 3,5-Dimethyl pyrazole 1 (2,3 g; 0.024 mole) in ethanol solution and triethylamine (6.65 g, 0.048 mole) were cooled to 5°C under stirring, then carbon disulfide (3.65 g, 0.048 mole) was added to the solution. After 1 hour of stirring, solid iodine (2,8 g, 0.022 mol) was added in portions and stirred until the colour disappeared completely. Then a methanolic solution of iodine was added dropwise until a faint colour persists. Excess of iodine was neutralised with Na₂S₂O₃solution. The product was extracted with diethyl ether, washed thrice with water, dried over Na₂SO₄, filtered, and diethyl ether was evaporated at room temperature to give compound 2 as a white solid. Yield: 93%.

Mp.: 87-89°C (diethyl ether/hexane: 8/2).

¹H-NMR (CDCl₃) d (ppm): 2,43 (s, 12H, CH₃); 6,00 (s, 2H, H_pyrazole).

¹³C-NMR(CDCl₃) d :193 ppm (-C=S), 150 (C₃), 148 (C₅), 110 (C₄), 12 (CH₃).

IR (KBr , cm^-1) : 3000 (-S-S-); 1290 (C=S).

MS (m/z): 342 [M]⁺.

U.V.: l_max = 285 nm (-C=S).

References

1. Jones, R. G.; Hanret, M. J.; Lauglin , K. M. J. Org . Chem. 1954, 19, 1428.
2. Haque, S.A.; Clouet, G., Makromol. Chem. Phys. 1994, 195, 315-327.
3. Reiser, A. Photoreactive Polymer. The Science and Technology of Resist; Wiley: New York, 1986, p. 26.
4. El Idrissi, A.; Tebbji, K.; Radi, S. Molecules 2001, 6, M232.

Sample Availability: Available from the authors and from MDPI.