Sustainable Synthesis and Polycondensation of Levoglucosenone‐Cyrene‐Based Bicyclic Diol Monomer: Access to Renewable Polyesters

The already‐reported, low‐yielding, and non‐sustainable Et3N‐mediated homocoupling of levoglucosenone (LGO) into the corresponding LGO‐CyreneTM diketone has been revisited and greened‐up. The use of methanol as both a renewable solvent and catalyst and K2CO3 as a safe inorganic base improved the reaction significantly with regards to yield, purification, and green aspects. LGO‐CyreneTM was then subjected to a one‐pot, H2O2‐mediated Baeyer–Villiger oxidation/rearrangement followed by an acidic hydrolysis to produce a new sterically hindered bicyclic monomer, 2H‐HBO‐HBO. This diol was further polymerized in bulk with diacyl chlorides to access new promising renewable polyesters that exhibit glass transition temperatures (Tg) from −1 to 81 °C and a good thermostability with a temperature at which 50 % of the mass is lost (Td50 %) of 349–406 °C. From cellulose to polyesters: The green homocoupling of cellulose‐derived levoglucosenone and subsequent Baeyer–Villiger oxidation provide a new 100 % bio‐based monomer (2H‐HBO‐HBO). This was then polymerized in the presence of diacyl chlorides to give a set of new sustainable polyesters with glass transition temperatures (Tg) between −1 and 81 °C and a temperature at which 50 % of the mass is lost (Td50 %) above 349 °C.