A fluorescence compound of benzocoumarin typical skeleton was synthesized and its interaction with various metal ions was evaluated. The synthesis was performed via Knoevenagel condensation whereas identification of the product was accomplished by various spectroscopic techniques. The chemo-sensor test against representative metal ions was monitored by fluorescence spectrophotometry. Density Functional Theory calculation (DFT) (Functional/basis set; M06/6-31G (d, p)) was also carried out to clarify the experimental results and to confirm the mechanism of interaction. The 3-oxo-3H-benzo[f]chromene-2-carboxylic acid 1 was obtained as yellow solid with; 60 % chemical yield, melting point; 235.6 - 236.7?C, ?max UV/Visible, ?em and Stokes shift (MeOH / nm); 374, 445, and 71 nm, respectively. Structure of the compound was identified based on spectroscopic data and literature comparison. The compound 1 exhibited a chelation quenched fluorescence (CHQF) phenomenon toward Na+ ion selectively, with binding stoichiometry (1:2) and LoD and LoQ of 0.14 and 0.48 mg/L, respectively. Based on DFT calculation, compound 1 chelated Na+ ion through mechanism of oxidative (1:1 equivalent) and reductive (2:1 equivalent) Photoinduced Electron Transfer (PET), correspondingly.
α-Hydroxyisovaleric acid (Ac-Hiv) and α-acetyloxyisovaleric acid (Ac-Hiv) have been successfully synthesized through a diazotisation of amino acid using sodium nitrite with the catalyst of sulfuric acid and acetic acid, respectively. In the synthesis of Hiv, Zubia et al. (2005) mentioned that 3 equivalents of sodium nitrite for the reaction gave the hydroxy acid with a good yield. However, Cohen-Arazi et al. (2008) described that 6 equivalents of sodium nitrite resulted the highest yield. In present study, a variation of equivalents of sodium nitrite (3, 4, 5, 6 eq.) were trialed for the same method of synthesis. Through several experiments, we found that 6 equivalents of sodium nitrite were the best portion among all. This finding was applied into the synthesis of protected Hiv (Ac-Hiv) that was previously reported by Maharani et al. (2017) giving 63% yield when 3 equivalent of sodium nitrite was employed. By increasing the equivalent of sodium nitrite into 6 equivalents, the Ac-Hiv can be synthesized with an improved yield (71%).
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.