Vibrational spectroscopic investigations, ab initio and DFT studies on 7-bromo-5-chloro-8-hydroxyquinoline

Comparative vibrational spectroscopic studies of 7-chloro-4- hydroxy-3-quinolinecarboxylic acid based on density functional theory

“…The C-H out-of-plane bending modes are observed in the region 950-600 cm −1 . The aromatic C-H out-of-plane bending vibrations of 7C4H3QCA are assigned to the bands observed at 976, 956, 880 and 831 cm −1 and these bands occurred in the said region [46][47][48]. The density functional theory analysis reveals that the aromatic C-H in-plane and out-of-plane bending vibrations have substantial overlapping with the ring C-C-C in-plane and out-of-plane bending modes, respectively.…”

Density functional theory, comparative vibrational spectroscopic studies, highest occupied molecular orbital and lowest unoccupied molecular orbital analysis of Linezolid

“…In FT-IR, frequency vibrations occurring at 3,180, 3,155 and 2,852 cm -1 are assigned to C-H vibrations and it shows good agreement with the literature data. The C-H in-plane and out-of-plane bending vibrations generally lie in the range 1,300-1,000 and 1,000-750 cm -1 [21,22], respectively. The FTIR bands at 1,273, 1,220, 1,143, 1,078 and 1,022 cm -1 and FT-Raman bands at 1,207, 1,118, 1,077, 1,049 and 1,024 cm -1 are assigned to C-H in-plane bending vibrations of the molecule.…”

Low-dimensional compounds containing bioactive ligands. Part III: Palladium(II) complexes with halogenated quinolin-8-ol derivatives

“…C-X stretching vibration usually manifests itself as strong absorption and the position of the band is influenced by neighboring atoms or groups; the smaller the halide atom, the greater the influence of the neighbor [32]. Thus, we suppose that stretching m(C 5 -X) vibrations for ClQ, dClQ, dBrQ and dIQ occur at 946, 954, 931 and 923 cm À1 , respectively.…”

“…2 and 3, respectively. The proposed assignment of the individual bands, which we were able to assign on the base of our previous experience [20,22] and available literature [26][27][28][29][30][31][32][33] is summarized in Table 2.…”

“…The assignment of individual bands in the IR spectra of halogenated derivatives of quinolin-8-ol was described only for 5-chloro-7-iodo-quinolin-8-ol (CQ) [20,22,31] and 7-bromo-5-chloro-quinolin-8-ol (BrClQ) [32], therefore we discuss also an assignment of individual bands for all used ligands in the syntheses. The IR spectra of these ligands differ slightly, however there are differences mainly in the m(C 5 -X) and m(C 7 -X) (X = Cl, Br or I)…”