Influence of reaction time and reactant ratio on the synthesis of hydroxyphenylglycine methyl ester (HPGME)

• Main Authors: Nuha, Nuha, Listiana, Shelvi, Bahua, Hismiaty, Rahayu, Maya D., Kusumaningrum, Susi, Marwoto, Bambang, Firdayani
• Format: Conference Proceeding
• Language: English
• Subjects: Amides; Amoxicillin; Esterification; Fourier transforms; Glycine; High performance liquid chromatography; Methanol; Reaction time; Sulfuric acid
• ISSN: 0094-243X; 1551-7616
• DOI: 10.1063/5.0173162

Hydroxyphenyl glycine methyl ester (HPGME) is an intermediate material needed, especially in the beta-lactam antibiotic production such as amoxicillin and cefadroxil. HPGME could be synthesized through the esterification reaction of hydroxyphenyl glycine (HPG) with methanol and a catalyst that typically used sulfuric acid. HPGME synthesis is influenced by several factors, such as reactant ratio and reaction time. In this study, HPGME synthesis was carried out at 75˚C for multiple reaction times: 30, 60, 90, and 120 minutes. This study also varied the HPG/methanol ratio used, there are 1 mol HPG with 7, 10, 14, and 17 mol methanol. Moreover, the purity of the samples and unreacted HPG were examined by High-performance liquid chromatography (HPLC). The confirmed structure was elucidated by Fourier transform infrared spectroscopy (FTIR). The results show that reaction time and reactant ratio influence the production of HPGME. After 90 minutes of synthesis, the yield increased significantly, almost 5-times. The reactant ratio of 1:10 mol with a reaction time of 120 min was achieved with a 34% yield, it was the highest one. Therefore, the optimum condition is reached when the longer reaction time with a suitable reactant ratio.