Levoglucosenone as a starting material for cascade continuous-flow synthesis of (R)-γ-carboxy-γ-butyrolactone.

The global imperative to shift towards renewable and sustainable resources has spurred significant interest in exploring and utilizing platform chemicals derived from renewable feedstocks. Among these, levoglucosenone (LGO) and Cyrene™ have emerged as promising candidates. LGO, derived from the pyrolysis of cellulose and hemicellulose, exhibits structural versatility, making it an attractive starting material for various valuable products. Its chemical transformations can yield a diverse array of derivatives, including levulinic acid, furan derivatives, and intermediates for pharmaceutical and agrochemical synthesis, as well as bio-based materials such as bioplastics and resins. Cyrene™, produced through the hydrogenation of LGO, serves as a renewable, biodegradable, and non-toxic dipolar aprotic solvent, offering sustainability advantages for green chemistry applications. Herein we report our results on the continuous-flow cascade transformation of LGO into Cyrene™ and then (R)-γ-carboxy-γ-butyrolactone in good yields with an additional mechanistic investigation for the Baeyer-Villiger oxidation of Cyrene™.