Chemical processing is a prolific field in South Africa’s National Research and Development Strategy and catalysis is central to the chemical industry, being fundamental to the production of value-added materials. With feedstocks such as alkanes and alkenes readily available, there is a need for the design and synthesis of new, more efficient and selective catalysts which will allow for conversion into more useful products and add value to hydrocarbon products. South Africa is also one the largest suppliers of Platinum Group Metals world-wide and there is a drive to find useful, value-added applications for these metals.
However, with the depletion of available PGM resources and the added expense of these metals, PGM recovery and sustainability remains a key issue for researchers. Over the past few years, our group has been involved in immobilising catalysts on polymeric/dendritic supports and in biphasic media. This not only combines the advantages of homogeneous and heterogeneous catalysis but allows for ease of separation of the reaction product from rreaction mixtures, facilitating recycling of the catalysts to avoid environmental toxicity and makes purification of products easier. The multinuclear catalysts may also display enhanced activity over mononuclear analogues. Applications of this work have been extended to various organic transformation reactions, in particular, hydroformylation and carbon-carbon coupling reactions.
Shepherd Siangwata, Nadia Baartzes, Banothile C.E. Makhubela and Gregory S. Smith
Synthesis, characterization and reactivity of water-soluble ferrocenylimine-Rh(I) complexes as aqueous-biphasic hydroformylation catalyst precursors