Synthesis, spectroscopic characterization, X-Ray analysis, and DFT-HF calculations of 5-ethoxymethyl-8-hydroxyquinoline

Abstract

5-ethoxymethyl-8-hydroxyquinoline was synthesized and characterized using spectroscopic methods ( 1 H, 13C NMR, IR). The crystal structure determined at room temperature (295 K) by means of X-ray powder diffraction is orthorhombic, with space group Pbca and eight molecules per unit cell (Z = 8, Z 0 = 1). The lattice parameters are: a = 7.9551(12) Å , b = 17.981(3) Å , c = 15.125(2) Å and V = 2163.5(6) Å 3 . Geometric parameters and properties depending on the charge distribution around the different types of donors and acceptors bonds within the molecule are calculated by density functional theory (DFT/B3LYP) and Hartree-Fock methods. Atomic charges and dipole moment value permit qualitative predictions about high reactivity of this molecule. The 5-ethoxymethyl-8-hydroxyquinoline adopts a non-planar structure in the solid state and the molecule is stabilized by contact system as p-p stacking interactions, weak intra and intermolecular H-Bonding O-HÁÁÁN and C-HÁÁÁO types, this latter involving the rings of both adjacent molecules in plans with a gap from 0.638 Å .

Recent Advances in the Synthesis and Biological Activity of 8-Hydroxyquinolines

“…Faydy and coworkers described the synthesis of new derivatives of 8-hydroxyquinoline ( 36 – 38 ) ( Figure 2 ) in a multistep approach [ 20 ] according to published procedures [ 21 , 22 , 23 ]. The antioxidant activity of prepared products, along with L-ascorbic acid, was evaluated by means of the free radical scavenging method using the 2,2-diphenyl-1-picryhydrazyl (DPPH) assay.…”

Corrosion Inhibition Studies of 8-Hydroxyquinoline Derivatives for N80 Steel in a 1.0 M HCl Solution: Experimental, Computational Chemistry, and Quantitative Structure–Activity Relationship Studies

“…38 The peaks at 1278, 1203, and 775 cm −1 were attributed to the C−N stretching vibration, C−O stretching vibration, and C−H bending vibration of the quinoline ring, respectively. 60 Compared with that of inhibitor 1, the peak intensity of inhibitor 2 at 3449 cm −1 decreased. A broad peak at 2725 cm −1 indicated the formation of hydrochloride, which concealed the absorption peak of the -CH 2stretching vibration.…”

“…In the Fourier transform infrared (FT-IR) spectrum of inhibitor 1 , the infrared absorption peak at 3449 cm –1 represented the O–H stretching vibration, and the peaks at 1579, 1500, and 1387 cm –1 corresponded to the skeleton vibration of the quinoline ring . The peaks at 1278, 1203, and 775 cm –1 were attributed to the C–N stretching vibration, C–O stretching vibration, and C–H bending vibration of the quinoline ring, respectively . Compared with that of inhibitor 1 , the peak intensity of inhibitor 2 at 3449 cm –1 decreased.…”