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

The already‐reported, low‐yielding, and non‐sustainable Et 3 N‐mediated homocoupling of levoglucosenone (LGO) into the corresponding LGO‐Cyrene TM diketone has been revisited and greened‐up. The use of methanol as both a renewable solvent and catalyst and K 2 CO 3 as a safe inorganic base improved the reaction significantly with regards to yield, purification, and green aspects. LGO‐Cyrene TM was then subjected to a one‐pot, H 2 O 2 ‐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 ( T g ) from −1 to 81 °C and a good thermostability with a temperature at which 50 % of the mass is lost ( T d50 % ) of 349–406 °C.