Thiadiazoles, computational studies

Rings incorporating [4 +2] rt-electrons are aromatic according to the Hiickel definition and on this basis 1,2,3-thiadiazoles can be considered as aromatic. This is supported by 13C and 111 NMR chemical shifts. In 1990, the aromaticities of some five- and six-membered ring heterocycles including 1,2,3-thiadiazole were studied by computational methods and found to correlate well with their chemical natures <1990JPR885>. 

A formally antiaromatic 1,4-dihydropyrazinothiadiazole has been prepared and characterized by single crystal X-ray spectroscopy. The antiaromatic character of which has been supported computationally using NICS measurements <20070L1073>. CHIH-DFT computational studies on acenaphtho[l,2-f]-l,2,5-thiadiazole 1,1-dioxide led to simulations of its infrared (IR) and ultraviolate (LJV) spectra, the dipole moment and polarizability <2007JMT373>. 4,6-Dinitrobenzothiadiazole was determined to have an electrophilic reactivity of —8.40 which corresponds to a pK z° of 7.86 for Meisenheimer complexation with water and is close to the demarcation boundary (E = —8.5) between super-and normal-electrophiles and between reactive dienophiles and inert partners in Diels-Alder adduct formation <20070BC1744>. 

Rodriguez-Calero GG, Lowe MA, Kiya Y et al (2010) Electrochemical and computational studies on the electrocatalytic effect of conducting polymers toward the redox reactions of thiadiazole-based thiolate compounds. J Phys Chem C 114(13) 6169-6176... 

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