Sustainable One-Pot Synthesis and Polycondensation of a Levoglucosenone-Derived Cyclic Acetal Diol

Abstract

The already described one-pot two-step hydration/reduction of levoglucosenone (LGO) into (1R,2S,5R)-6,8-dioxabicyclo­[3.2.1]­octane-2,4-diol (HO-LGOL) was improved by replacing 50 mol % of Et3N by 5 mol % of K3PO4, a more sustainable base. The sterically hindered diol was then subjected to polycondensations with aliphatic comonomers to prepare new bio-based polyesters that exhibit glass transition (T g) values between 12 and 54 °C and high thermal stability greater than 200 °C. Two different strategies were implemented to perform the polymerizations: (1) utilization of aliphatic diacyl chlorides, or (2) a method involving aliphatic diethyl esters in the presence of a metal catalyst. These methods were then subjected to life cycle assessment to study their environmental impacts.

Levoglucosenone to 3D-printed green materials: synthesizing sustainable and tunable monomers for eco-friendly photo-curing

“…However, a successful one-pot two-step oxa-Michael addition followed by the Baeyer–Villiger oxidation has been previously described. 11 Nevertheless, the direct addition of hydrogen peroxide in the presence of a large excess of allyl alcohol was not efficient, probably due to the high dilution of the reaction medium that prevented oxidation. In consequence, allyl alcohol was distilled from the crude mixture prior to the addition of H 2 O 2 .…”

“…8 Recently, we have been concentrating on developing new types of functional monomers using LGO, taking advantage of its highly reactive functionalities and commercial availability (currently at 50 T per year and soon increasing to 1000 T per year). These new LGO polymer derivatives include polyacrylates, 9 polycyclic olefins, 10 polyesters, 11,12 and polycarbonates. 13 However, until now, the controlled formation of polymer networks derived from LGO-based monomers has not been reported.…”

Levoglucosan and levoglucosenone as bio-based platforms for polymer synthesis

“…The authors studied the environmental impacts of the polycondensation processes, confirming that the impact of the solvent (ethanol) used is more significant than the nature of the specific reagents. 51 As discussed above, Cyrene™, is the hydrogenation product of levoglucosenone. Both literature reports and patents present methods to produce homo and co-polymers, derived from Cyrene™.…”

“…The authors studied the environmental impacts of the polycondensation processes, confirming that the impact of the solvent (ethanol) used is more significant than the nature of the specific reagents. 51…”

“…The monomer, HO-LGOL, was then used to form polyesters via polycondensation. 51 Aliphatic co-monomers were used to prepare the bio-based polyesters. The resulting polymers possessed high thermal stabilities and glass transition temperatures between 12 and 54 °C, however the degradability of these materials was not reported.…”