Vol.:(0123456789) SN Applied Sciences (2020) 2:1019 | https://doi.org/10.1007/s42452-020-2782-4 Research Article Economical synthesis strategy, characterization and theoretical study of the organic dye 3‑oxo‑3H‑spiro [isobenzofuran‑1,9′‑xanthene]‑3′,6′‑ diyl dibenzoate Nadia Arrousse 1  · El Houssine Mabrouk 1,2  · Khadija Ismaily Alaoui 1  · Fadoua El Hajjaji 1  · Zakia Rais 1  · Mustapha Taleb 1 Received: 19 February 2020 / Accepted: 15 April 2020 / Published online: 5 May 2020 © Springer Nature Switzerland AG 2020 Abstract In the present work, the economical synthesis strategy of the compound in high yield was reported through the reaction between fuorescein and benzoyl chloride under diferent operating conditions. The synthesized compound: 3-oxo-3H- spiro[isobenzofuran-1,9′-xanthene]-3′,6′-diyldibenzoate was characterized by IR, 1 H NMR, 13 C-NMR and mass spectral. This reaction has been studied also theoretically using Gaussian 09 based on the DFT method at B3LYP/6-311G (d, p). The results revealed that the theoretical study is in good correlation with the experimental one. The analysis of the absorption spectrum shows that the prepared product which has optical properties is a colored pigment. Keywords O-benzoylation · Fluorescein · Benzoyl chloride · DFT/B3LYP method/6-311G base (d, p) 1 Introduction The chemistry of heterocyclic compounds has received much attention owing to its synthetic and efective bio- logical importance [1–9]. They have been incorporated into a variety of therapeutically appealing drug candi- dates including antiviral, anti-migraine, antifungal, anti- anxiety compounds. The heterocyclic chemistry occupies a prime place in medicinal and pesticide chemical science due to their capability to exhibit a wide range of bioac- tivities, such as antimicrobial [10–14], anticancer [15], anti- infammatory [16, 17], antidepressant [18], anticonvulsant [19], antipyretic [20], selective enzyme inhibitory activities [21], etc. Fluorescence typically occurs in aromatic molecules and heterocycles, called fuorophores or fuorescent dyes. Fluo- rescent particles always contain a chromophore, the part of a molecule responsible for its color. These endogenous fuorophores are responsible for the autofuorescence of biological structures like mitochondria or lysosomes [22]. Polycyclic aromatic compounds represent a class of fuo- rescent dyes widely applied as useful synthetic biomol- ecule labels [23, 24]. Our team has been investigating the fuorescein for their biological activity for several years. The development of efcient methods for the formation of the C-O bond via the acylation of O–H bonds is one of the pri- mary subjects in organic synthetic chemistry. Because of these and the continuation of our research, the synthesis of heterocyclic systems of xanthene derivations and bio- logically active molecules, we hereby report the prepa- ration of new fuorescein derivative and the theoretical study of its reaction. 3-oxo-3H-spiro[isobenzofuran-1,9′-xanthene]-3′,6′-diyl (3-dibenzoate) previously synthesized by Hossein Eshghi * El Houssine Mabrouk, mabrouk.elhoussine@gmail.com | 1 Laboratory of Engineering, organometallic, Molecular and Environment (LIMMOME), Faculty of Sciences, University Sidi Mohamed Ben Abdellah, Fez, Morocco. 2 Laboratory of Materials Engineering for the Environment and Natural Resources, Department of Chemistry, Faculty of Sciences and Technics, Moulay Ismail University Meknes, BP 509 Boutalamine, Errachidia, Morocco.