James W. Comerford

Sustainable metal-based catalysts for the synthesis of cyclic carbonates containing five-membered rings

The use of sustainable metal-based catalysts for the synthesis of five-membered ring containing cyclic carbonates from epoxides and carbon dioxide is critically reviewed. Coverage is restricted to catalysis by the abundant metals: sodium, potassium, aluminium, calcium, titanium and iron and the relative merits and limitations of each catalyst system are compared.

Homogeneous and silica-supported zinc complexes for the synthesis of propylene carbonate from propane-1,2-diol and carbon dioxide

Three organozinc complexes have been synthesised and found to catalyse the carbonylation of propylene glycol with carbon dioxide to form propylene carbonate. A similar tethered organozinc complex was supported onto high loading aminopropyl functionalised hexagonal mesoporous silica and was also found to be catalytically active.

Quinine catalysed asymmetric Michael additions in a sustainable solvent

Diethyl carbonate is shown to be a suitable, sustainable solvent in which to carry out quinine catalysed asymmetric Michael additions of malononitriles to enones. Both malonitrile and α-substituted malononitriles can be used as substrate and the results suggest that π–π stacking interactions between the (hetero)aromatic rings of the catalyst and substrates are important in determining the degree of asymmetric induction.

Green Catalytic Transformations

With ever-increasing demand of chemical products on a global scale, as well as poor public image in recent years, there has been increasing pressure for chemistry industry to become more efficient and sustainable.

Insights into Post-polymerisation Modification of Bio-based Unsaturated Itaconate and Fumarate Polyesters via Aza-Michael Addition: Understanding the Effects of C=C Isomerisation

ABSTRACT Development of renewable bio‐based unsaturated polyesters is undergoing a renaissance, typified by the use of itaconate and fumarate monomers. The electron‐deficient C=C bond found on the corresponding polyesters allows convenient post‐polymerisation modification to give a wide range of polymer properties; this is notably effective for the addition of nucleophilic pendants. However, preservation of unsaturated functionality is blighted by two undesirable side‐reactions, branching/crosslinking and C=C isomerisation. Herein, a tentative kinetic study of diethylamine addition to model itaconate and fumarate diesters highlights the significance of undesirable C=C isomerisation. In particular, it shows that reversible isomerisation from itaconate to mesaconate (a poor Michael acceptor) is in direct competition with aza‐Michael addition, where the amine Michael donor acts as an isomerisation catalyst. We postulate that undesired formation of mesaconate is responsible for the long reaction times previously reported for itaconate polyester post‐polymerisation modification. This study illustrates the pressing need to overcome this issue of C=C isomerisation to enhance post‐polymerisation modification of bio‐based unsaturated polyesters.