UV/VIS absorption and fluorescence spectroscopic study of some 3‐substituted derivatives of 4‐hydroxycoumarin
Purpose – The purpose of this paper is to test absorption characteristics of some newly synthesised 4‐hidroxycoumarins, containing phenyl‐prop‐2‐enoyl group at the 3‐position. Change in spectral characteristics in solvents of different polarity (chloroform and acetonitrile) was followed in regard to the influence of the substitution at the phenyl ring and influence of concentration H+ ions. Effectiveness of tested substances was compared with well‐known UV absorbers such as benzophenone‐3 and butyl methoxydibenzoylmethane (BMDM).Design/methodology/approach – All the tested substances were dissolved in chloroform and acetonitrile, with 10‐3 mmol concentration range. The pH was adjusted using 0.1 mol/l HCl, glacial acetic acid, 0.1 mol/l NaOH (aqueous solution) and 0.1 mol/l NaOH (methanolic solution). Spectrophotometric measurement was recorded in the range of 200‐800 nm, using 1‐cm quartz cells.Findings – The tested 4‐hydroxycoumarin derivatives showed good UV absorption properties in the range 280‐380 nm...