title: Novel olefinic-centered macroacyclic compounds involving tetrasubstituted 4-hydroxybenzoic acid fragments: synthesis, structural characterization and comparison of experimental and computational results.
abstract: Dialkyl 4,4'-(2-(1,3-bis(4-(alkoxycarbonyl)phenoxy)propan-2-ylidene)propane-1,3-diyl)bis (oxy)dibenzoate 6a,b were synthesized through the reaction of ethene-1,1,2,2,-tetra-yl-tetra methylene tetra bromide 1 with methyl 4-hydroxy benzoate or ethyl 4-hydroxy benzoate 2a,b. In addition, compounds 6a,b were obtained by using the esterification reaction from the reaction compound 5 with methyl and ethyl alcohol in high yields. Compound 4 was synthesized from the reaction of ethene-1,1,2,2,-tetra-yl-tetra methylene tetra bromide 1 with 4-hydroxy benzonitrile 3. The structures of the novel synthesized compounds were confirmed by IR, (1)H NMR, (13)C NMR, COSY, elemental analysis, and mass spectral data. Compound 6b, C42H44O12, was also characterized with additional analysis such as UV-vis, and X-ray spectral techniques. The electronic structure of compound 6b was studied by DFT level 6-31G∗(d,p) using X-ray crystallographic data. The results obtained from this study are consistent with the X-ray data. In order to understand the electronic transitions of the compound 6b, time dependent density functional theory (TD-DFT) calculations were carried out. TD-DFT studies showed that the low-energy excitations are consistent with the experimental results.
authors.affiliation: Department of Chemistry, Faculty of Science, Karabuk University, 78050 Karabuk, Turkey. Electronic address: mustafaer@karabuk.edu.tr.
authors.forename: Mustafa
authors.initials: M
authors.lastname: Er
authors.affiliation: Department of Chemistry, Faculty of Arts and Sciences, Karadeniz Technical University, 61080 Trabzon, Turkey. Electronic address: ismail61@ktu.edu.tr.
authors.forename: İsmail
authors.initials: İ
authors.lastname: Değirmencioğlu
authors.affiliation: Department of Polymer Engineering, Faculty of Technology, Karabuk University, 78050 Karabuk, Turkey. Electronic address: hakantahtaci@karabuk.edu.tr.
authors.forename: Hakan
authors.initials: H
authors.lastname: Tahtacı
mesh_terms: D000475:Alkenes / Q000737:chemistry*; D018360:Crystallography, X-Ray; D004583:Electrons; D006860:Hydrogen Bonding; D047028:Macrocyclic Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D008958:Models, Molecular; D008968:Molecular Conformation; D010226:Parabens / Q000737:chemistry*; D011789:Quantum Theory; D013056:Spectrophotometry, Ultraviolet
chemical_list: D000475:Alkenes; D047028:Macrocyclic Compounds; D010226:Parabens
keywords: Crystal structure; DFT; Parabens; UV–vis; p-Hydroxybenzoic acid esters