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Impedance Spectroscopy and Spectroscopy on Polymeric Nanofibers
Published in A. Sezai Sarac, Nanofibers of Conjugated Polymers, 2017
Anthranilic acid (o-amino benzoic acid) is an important monomer for the synthesis of carboxylic acid group–substituted PANI (Fig. 6.15). Studies on the synthesis of poly(anthranilic acid) (PANA) from an aqueous acidic solution are scarcely reported in the literature, probably because of difficulty in synthesis, poor yield, and brittle nature of the film due to presence of an electron-withdrawing carboxylic group. PANA reveals high solubility in an aqueous solution of NaOH or NMP.178 Similar to poly(metanilic acid), PANA exhibits electrochemical activity over a wide pH range in aqueous solutions owing to the substitution of the carboxylic acid group.
Green chemistry approach to the synthesis of 3-substituted-quinazolin-4(3H)-ones and 2-methyl-3-substituted-quinazolin-4(3H)-ones and biological evaluation
Published in Green Chemistry Letters and Reviews, 2020
Mario Komar, Maja Molnar, Marijana Jukić, Ljubica Glavaš-Obrovac, Teuta Opačak-Bernardi
Compounds 5–10 are synthesized in ChCl:U (1:2) DES at 80°C. First, benzoxazinone (I) was synthesized conventionally, according to the well-known procedure, from anthranilic acid and acetic anhydride (38). A proposed mechanism for the synthesis of benzoxazinone is shown in Figure 5. First acetylated anthranilic acid is formed through the nucleophilic attack of the amine to the carbon atom and subsequent formation of acetic acid. Cyclization of N-acetyl anthranilic acid and further elimination of water molecule yields the final product 2-methyl-benzoxazinone I.
Interaction of organic pollutants with TiO2: a density functional theory study of carboxylic acids on the anatase (101) surface
Published in Molecular Physics, 2023
Manasi R. Mulay, Natalia Martsinovich
Our results show that all of the investigated structures are strongly adsorbed, with large negative adsorption energies of the order of −1 eV. The adsorption energies are slightly (by 0.01-0.15 eV) more negative in the (2 × 3) and (1 × 6) extended surface unit cells (Table S2); however, the trends in adsorption stabilities are not affected by the cell size. We find that aromatic acid molecules (benzoic, nicotinic, salicylic and anthranilic acid) are more strongly adsorbed than formic acid. For example, for the dissociative bridging-bidentate structure DB, the strength of adsorption increases in the sequence FA < BA < SA ≤ NA < AA. A similar trend can be seen in the monodentate structures M1-M4, where the strength of adsorption increases as FA < SA < BA < NA < AA. This sequence of adsorption energies is consistent with the surface-adsorbate Ti-O distances (Table 2), which are longer for adsorbed FA than for aromatic acids (except some SA configurations) by up to 0.10 Å. This trend in the strengths of adsorption can be attributed to the electron-withdrawing nature of the phenyl group, which strengthens the partly ionic bonding between carboxylic oxygens and surface Ti4+ ions and thus makes the adsorption of aromatic acids stronger. Additionally, the higher electronegativity of O and N than C makes the aromatic groups of NA, SA and AA more electron-withdrawing than BA, thus accounting for the stronger adsorption of NA, SA and AA. In particular, the adsorption configurations of nicotinic acid are very similar to benzoic acid, but nicotinic acid is systematically 0.06–0.08 eV more strongly adsorbed. This trend suggests that changes to the aromatic ring not next to the anchoring group do not have a qualitative effect on adsorption configuration, but they may affect the strength of adsorption.