Examination with DFT, Raman, FT-IR and NMR spectroscopic methods of some boronic acid and its derivatives as theoretical and experimental

The most stable state of some boronic acid derivatives such as 2-fluoro-3-methyl pyridine-5-boronic acid, 6-bromo-3-pyridinil boronic acid, 4 carboxy-3-phenyl boronic acid and 3-acrylamido phenyl boronic acid were calculated with Gaussian 09 programme and using 6-311++G(d,p) basis set, B3LYP method. 1H, 13C, 13C APT, 1H coupled 13C, COSY and HETCOR NMR spectra of these molecules were measured by solving in d6-DMSO. 13C CP/MAS NMR spectra of samples were obtained. 13C and 1H NMR chemical shift values of these molecules were calculated theoretically using the same basis set. After UV-VIS spectra experimentally obtained in various solvents, theoretical spectrum was obtained using B3LYP method, 6-311++G(d,p) basis set and electronic transitions were constituted with Gaussam 2.0 program. FT-IR, Raman, vibrational assigments, XRD measurements and HOMO-LUMO calculations and molecular orbital analysis were carried out. Some J coupling values of these molecules were determined experimentally in DMSO solvent. Moreover, some geometric parameters such as bond lengths and bond angles of these molecules were determined using DFT/B3LYP method, 6-311++G(d,p) basis set. Keywords: Boronic acid derivatives, NMR, IR, Raman, UV/VIS, DFT.