Efficient One-Step Synthesis of Lactide with High Yield and Selectivity Using Brønsted Acid Catalysis
Wenqi Qiu1, Yukang Liu1, Yufei Zhang1
1Engineering Research Center of High-Performance Polymer and Molding Technology, Ministry of Education, Qingdao University of Science and Technology, Qingdao, 266042, China.
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In this work, a one-step method synthesis of lactide is reported instead of the traditional two-step method. The selection of a suitable acid catalyst polyphosphoric acid and optimization of reaction conditions result in a yield of 97%. Moreover, this new one-step strategy eliminates the need for metal catalysts and does not require high-temperature conditions, thereby avoiding the issue of racemization. The simple one-step strategy offers a combination of efficiency, sustainability, and product quality improvements, making it a modern, practical approach to lactide synthesis.
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