DFT, ab initio and FT-IR studies of the structure of sulfonamide triazenes

We present an in-depth investigation of the structural, infrared spectra and visible spectra of various triazenes with a sulfonamide moiety. The preparation of 4-sulfonyl amide benzenediazonium chloride with cyclic amines of various ring sizes (pyrrolidine, piperidine, 4-methylpiperidine, N-methylpiperazine, morpholine and hexamethyleneimine) are theoretically investigated using the density functional theory (DFT) and Hartree-Fock (HF) levels of theory with the standard 6-31G* basis set. The calculated vibrational frequencies are evaluated via comparison with experimental values. The vibrational spectral data obtained from solid-phase FT-IR spectra are assigned modes based on the results of the theoretical calculations. The UV-Vis spectrum of each compound is measured in various solvents with a wide range of polarity to examine the role of solvent chemistry on observed spectral changes. The calculated spectra are in good agreement with the experimental spectra.