Efficient synthesis, spectroscopic characterization and DFT based studies of novel 1-amide 4-sulfonamide-1,2,3-triazole derivatives

In the present study, for the first time 1-amide 4-sulfonamide-1,2,3-triazole scaffolds were synthesized by using an azide-alkyne Huisgen cycloaddition reaction. The target products were obtained in moderate to good yields (45-75%) by using catalytic Cul and green system H2O/EtOH. The easy availability of the inexpensive starting materials, avoiding isolation and handling of hazardous organic azides and mild reaction conditions make this method a valuable tool for generating functionalized 1,2,3-triazole derivatives. The unambiguous characterization of synthesized compounds was accomplished by using various spectroscopic techniques such as H-1 NMR, C-13 NMR, and FT-IR. The information regarding optimized geometry, were obtained by applying DFT/B3LYP-6-31G(d) method. The electrophilicity index, H-1 and C-13 chemical shift values, lithium and sodium ion affinities of the desired product 3b have been also calculated by the mentioned method. As a whole, the calculated results were found in close agreement to that of experimental data. The studies revealed that the compound 3b possesses good Li+ and Na+ affinity and cation pi interaction plays a vital role in the complexation of 3b. For the first time, nucleus-independent chemical shift index was used to confirm the cation pi interaction of 3b. (C) 2019 Elsevier B.V. All rights reserved.