Regioselective synthesis and DFT computational studies of novel β-hydroxy-1,4-disubstituted-1,2,3-triazole-based benzodiazepinediones using click cycloaddition reaction

Novel β-hydroxy-1,4-disubstituted-1,2,3-triazole-based benzodiazepinedione derivatives were synthesized by a regioselective cascade reaction and were fully characterized by HRMS, FT-IR, 1H NMR, and 13C NMR measurements. The cascade reaction consists of the azidation of epoxides and the Huisgen [3+2] dipolar cycloaddition of the resulted β-hydroxy azides with the N,N′-dipropargyl benzodiazepine to give the wished 1,2,3-triazole-based benzodiazepinedione derivatives. Good yields (60–85%), easily available and inexpensive starting materials, using water as a green solvent, and avoiding the handling of organic azides as they are generated in situ are the advantages of this method. Theoretical calculations were also conducted by the DFT method using the B3LYP functional and 6-31+G(d,p) basis set on structure to characterize structure 3a. For structural and electronic characterization, 1H and 13C chemical shifts were calculated by the computational method and interpreted. The DFT calculated data were in line with the experimental data.