The flavanone glycoside naringin, which is abundant in the very immature pomelo peel cultivated in Vietnam, has been demonstrated to have potential use in semisynthesis into other flavonoid compounds, especially apigenin, which exhibits several biological properties and has a greater commercial value. In this study, we carried out an oxidation reaction on flavanone backbone to semisynthesize apigenin with I2 catalyst in some environmentally friendly solvents such as a replacement for the reaction in the pyridine solvent, which is thought to be a non-green solvent. | Cite this paper Vietnam J. Chem. 2023 61 S2 137-142 Research Article DOI Green approach to semisynthesis of apigenin from naringin isolated from very immature pomelo peels Nguyen Khanh Hung1 2 Nguyen Tuan Thanh1 2 Nguyen Thi Thuy Luyen1 2 4 Nguyen Huy Du1 2 3 1 Faculty of Chemistry University of Science 227 Nguyen Van Cu Road District 5 Ho Chi Minh City 70000 Viet Nam 2 Vietnam National University of Ho Chi Minh City Vo Truong Toan Road Linh Trung Ward Thu Duc City Ho Chi Minh City 70000 Viet Nam 3 Central Laboratory of Analysis University of Science 227 Nguyen Van Cu Road District 5 Ho Chi Minh City 70000 Viet Nam 4 Faculty of Geology University of Science 227 Nguyen Van Cu Road District 5 Ho Chi Minh City 70000 Viet Nam Submitted February 22 2023 Revised April 16 2023 Accepted May 28 2023 Abstract The flavanone glycoside naringin which is abundant in the very immature pomelo peel cultivated in Vietnam has been demonstrated to have potential use in semisynthesis into other flavonoid compounds especially apigenin which exhibits several biological properties and has a greater commercial value. In this study we carried out an oxidation reaction on flavanone backbone to semisynthesize apigenin with I 2 catalyst in some environmentally friendly solvents such as a replacement for the reaction in the pyridine solvent which is thought to be a non-green solvent. These solvents which were employed in this investigation included water DMSO ethyl acetate ethanol ethylene glycol and vegetable oil. The degree of conversion and the purity of the isolated product were evaluated using the RP-HPLC-DAD method the yield was calculated according to the mass of the obtained crystals and the synthetic compounds were confirmed by NMR spectra. The results showed that the solvents of DMSO DMSO H 2O gave the total yield of 93 and the purity of apigenin greater than 95 as compared to 74 and 93 respectively with the reaction in pyridine. Our findings revealed that .