Structural, spectroscopic and theoretical studies on dixanthogens: (ROC(S)S) 2 , with R = n-propyl and isopropyl

• Published in: New journal of chemistry 2014, Vol.38 (8), p.3708-3716
• Main Authors: Juncal, Luciana C., Tobón, Yeny A., Piro, Oscar E., Della Védova, Carlos O., Romano, Rosana M.
• Format: Article
• Language: English
• ISSN: 1144-0546; 1369-9261
• DOI: 10.1039/C4NJ00708E

Structural and conformational properties of two dixanthogen molecules, [CH 3 (CH 2 ) 2 OC(S)S] 2 and [(CH 3 ) 2 CHOC(S)S] 2 , have been analyzed using a combined experimental and theoretical approach, with data obtained from structural X-ray diffraction methods, IR, Raman and UV-visible spectroscopies, and DFT calculations. [(CH 3 ) 2 CHOC(S)S] 2 crystallizes in the monoclinic P 2 1 / c space group with a = 9.735(1) Å, b = 12.588(3) Å, c = 12.131(2) Å, β = 112.65(1)°, and Z = 4 molecules per unit cell. The interactions in the crystal were modelled and interpreted by NBO analysis. [CH 3 (CH 2 ) 2 OC(S)S] 2 is liquid at room temperature, and the vibrational spectra were satisfactorily explained in terms of the equilibrium between three conformers, originating from the rotation of the two terminal CH 3 – groups, in agreement with the DFT predictions. The electronic spectra of both dixanthogens were assigned with the assistance of the TD-DFT calculations.