The usage of renewable resources has become a hot topic upon the rising global awareness against fossil feedstock consumption. Lignin, the 2nd most abundant natural polymer on Earth, is an...

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Cellulose-derived photocrosslinkable polycarbonates (PCs) with renewable citronellol pendant chains were synthesised through the polycondensation of Triol-citro, a recently developed levoglucosenone-based triol monomer, and dimethoxycarbonyl isosorbide. The polymer structures were unveiled...

New mixed allyl−borohydrido lanthanide complexes Ln(BH 4 ) 2 (C 3 H 5 )(THF) 3 (Ln = Nd (1), Sm (2)) could be prepared in good yield by reacting Ln(BH 4 ) 3 (THF) 3 (Ln = Sm, Nd) with 1/2 equiv of Mg(C 3 H 5 ) 2 (THF) x . X-ray structure analysis revealed monomeric structures with two terminal BH 4 ligands, one π-allyl ligand, and three THF molecules. In an assessment of isoprene polymerization, 1 afforded trans-1,4-polyisoprene in good yield, as a single component or in combination with Mg cocatalyst. Both 1 and 2 were found to be extremely active toward ε-caprolactone polymerization.

Levoglucosenone (LGO) is a cellulose-derived molecule that is present commercially on a multi-ton/year scale. Taking advantage of the α,β-conjugated ketone of LGO, a new citronellol-containing 5-membered lactone (HBO-citro) was synthesized through a one-pot two-step pathway involving oxa-Michael addition and Baeyer-Villiger oxidation. The solvent-free treatment of HBO-citro with NaBH4 at room temperature led to the full reduction of the lactone moiety which gave a novel fully renewable triol monomer having a citronellol side chain (Triol-citro). Noticeably, by simply changing the reducing agent, temperature and reaction duration, the partial reduction of HBO-citro can be achieved to yield a mixture of 5- and 6-membered Lactol-citro molecules. Triol-citro was chosen to prepare functional renewable polyesters having citronellol pendant chains via polycondensation reactions with diacyl chlorides having different chain lengths. Good thermal stability (Td5% up to 170 °C) and low glass transition temperatures (as low as −42 °C) were registered for the polyesters obtained. The polymers were then hydrolyzed using a commercial lipase from Thermomyces lanuginosus (Lipopan® 50 BG) to assess their biodegradability. A higher degradation profile was found for the polyesters prepared using co-monomers (acyl chlorides) having longer chain lengths. This is likely due to the decreased steric hindrance around the ester bonds which allowed enhanced accessibility of the enzyme.

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.

This mini-review focuses on recent advances on the synthesis, structure, and characterization of allyl-based rare earth organometallic complexes, with emphasis on their ability to catalyze the polymerization of non-polar monomers such as conjugated dienes, styrene, and their related copolymerization.

The levoglucosenone-based norbornenes family was extended to include a new bi-functional methacrylate monomer that, upon ROMP in Cyrene™, leads to polymers with pendent methacrylate moieties which can be modified by post-polymerization reactions.