Benzyl lactate (BL) is a critical reagent in pharmaceutical and chemical synthesis due to its versatility. Traditional synthesis of BL was constrained by the high cost and low yield, thereby hindering the feasibility of large-scale production. Here, we reported a novel synthesis strategy for BL by utilizing the alcoholysis of waste polylactic acid (PLA) by benzyl alcohol with the protic ionic salt, HTBD-OAc, as the catalyst. The gram-scale experiments achieved a 94.9 % yield, and the robustness of this reaction was evidenced by the yield maintaining 92.5 % across six recycling experiments. More impressively, kilogram-scale synthesis facilitated a complete conversion of PLA to BL, achieving an unprecedented yield of 98.7 % at 180 °C within two hours. The exceptional catalytic efficiency of this reaction is attributed to the synergistic functions between the HTBD+ cation and OAc− anion in the catalyst HTBD-OAc. This study heralds a significant stride towards the sustainable and scalable production of high-purity benzyl lactate, paving the way for extended industrial applicability for this essential compound.
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