THE INFRARED SPECTRA OF 4-SUBSTITUTED-THIOSEMICARBAZIDES AND DIAZOTIZATION PRODUCTS

The infrared absorption spectra of 4-substituted-thiosemicarbazides, 5-(substituted)amino-1,2,3,4-thiatriazoles, and the corresponding isomeric tetrazolinethiones have been studied and structural assignments of importance to these systems made or suggested. Important conclusions drawn from the spectral data are: there is no suggestion of any thiol-thione tautomerism for the solid 4-substituted-thiosemicarbazides and that the thione structure predominates for these substances; that the so-called 5-thiol-tetrazoles also exist as thiones; and that the diazotization products of the 4-substituted-thiosemicarbazides yield 1,2,3,4,-thiatriazoles rather than the isomeric open chain thiocarbamyl azides. The C==S, NC==S, and cyclic NN==N configurational assignments, which are of importance to the classes of compounds studied, are discussed.