One-step synthesis of stereo-pure l,l lactide from l-lactic acid

Poly (lactic acid) (PLA) is extensively used as an eco-friendly compound for many applications. The synthesis of stereo-pure lactide, specifically l , l -lactide which is the most desired isomer for the synthesis of high-quality PLA is very important. In this work, various materials including MOFs and simple bases have been applied as catalysts for the Lactide synthesis. Herein we report the one-step synthesis of l , l -lactide with high selectivity and yield (99%) in the absence of racemization by applying a cost-effective Cs 2 CO 3 catalyst. The novel described procedure is even expected to be very efficient for industrial applications.