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Methyl vinyl glycolate (MVG) can be obtained by acid-catalyzed conversion of C4 and C6 sugars. Applications of MVG in polymers are so far limited to its use as co-monomer for poly(lactic acid) and as crosslinking agent. In this work, hydroformylation and methoxycarbonylation of MVG were investigated to produce novel bifunctional monomers. Polyesters with high renewable-atom content were successfully prepared and characterized. [ABSTRACT FROM AUTHOR]

Industrially relevant intermediates such as malonic acid, malonates and 3-oxopropionates can be easily accessed by ozonolysis of α-angelica lactone, derived from the platform chemical levulinic acid. The roles of the solvent and of the quenching conditions are of key importance for the outcome of the reaction. [ABSTRACT FROM AUTHOR]

Diols prepared via solvent-free acetalisation of hydroxymethylfurfural with glycerol were incorporated as additives into polyurethanes based on a bioderived polyether polyol. Moisture-cured as well as acrylate cross-linked films of these PUs were prepared. Both materials displayed excellent thermal stability and could be cleaved in acidic solutions. In particular the highly cross-linked film produced from the acrylate endcapped polyurethanes displayed a clear tuneability of the degradation behaviour according to the amount of acetal additive incorporated. This system has the potential to be used for the selective debonding of polyurethane-based adhesives at the end of their lifetime to facilitate the recycling of expensive components and raw materials from complex devices such as consumer electronics. [ABSTRACT FROM AUTHOR]

Bio-based levulinic acid is easily ring-closed to α-angelica lactone (α-AL). α-AL can be isomerized to the conjugated β-AL under the influence of base, but since this is an equilibrium mixture it is very hard to devise a scalable process that would give pure β-AL. This problem was circumvented by distilling the equilibrium mixture to obtain a 90 : 10 mixture of β- and α-AL in 88% yield. This mixture was used for Diels–Alder reactions on 3 terpenes and on cyclopentadiene in up to 100 g scale. The latter DA adduct was subjected to a ROMP reaction catalysed by the Grubbs II catalyst. The resulting polymer has some similarities to poly-norbornene but is more polar. The polymer can be processed into films with very good transparency. [ABSTRACT FROM AUTHOR]

Allylic alcohols are highly important compounds which are used in a variety of processes. They can be obtained from α,β-unsaturated carbonyl compounds via stoichiometric or catalytic reductions. Catalytic transfer hydrogenation is a safe and convenient method to use for this purpose since it circumvents the use of hydrogen gas or stoichiometric amounts of hydride-containing reducing agents. Apart from the benefits regarding safety and costs, it also provides an extra handle for the chemist for improving rate and selectivity as different reducing agents, such as secondary alcohols or formate salts can be used. In addition, there is a very wide range of catalysts, homogeneous and heterogeneous, to choose from. This review covers the literature of the past 30 years on metal-catalysed transfer hydrogenation of α,β-unsaturated ketones and aldehydes to unsaturated alcohols using homogeneous or heterogeneous catalysts. [ABSTRACT FROM AUTHOR]