Optimal Synthesis of Carboxyethylgermanium Sesquioxide From GeO 2 Based on Single Factor Experiment and Response Surface Method
Longyu He, Shiyan Wu, Shiji Fu, Bingjie Jin, Yuhui Zhang, Jinlei Yang, Qiyou Chen, Xian Zhong, Dong Li, Yao Deng, Ruixue YangABSTRACT
Organogermanium compounds, particularly carboxyethylgermanium sesquioxide (Ge‐132), have attracted increasing interest in biomedical and healthcare fields due to their reported antitumor, cancer‐preventive, and immunomodulatory activities. Previous studies merely reported the synthesis of this product without exploring feasible parameters for industrial routes. For the first time, this work combines single‐factor experiments and response surface methodology (RSM) to systematically optimize the critical process parameters for Ge‐132 synthesis from GeO 2 through the GeHCl 3 intermediate. The optimal reduction conditions were determined to be a GeO 2 /NaH 2 PO 2 mass ratio of 1:1.5, 5.1 equivalents of concentrated HCl, a reaction temperature of 84°C, and a reaction time of 3.5 h. The addition reaction was optimized at 1.1–1.2 equivalents of acrylic acid, 40°C, and 0.5 h, followed by hydrolysis of 3‐(trichlorogermyl) propionic acid at a solid–liquid ratio of 1:7–1:8 for 2 h. Under the overall optimized conditions, the Ge‐132 yield exceeded 83%. The product was characterized by elemental analysis, FT‐IR, XRD, and 1 H NMR, confirming a composition of 21.33% C, 2.81% H, and 42.62% Ge, and there are no by‐products and all impurity elements meet various standards. This method demonstrates high production efficiency and provides a promising basis for scaling up Ge‐132 synthesis from laboratory to industrial production.