A major focus of green and sustainable chemistry research has been to try to find ways to produce the same chemicals we use today from sustainable sources. Such a challenge usually involves the deconstruction and major modification of biomass’s three constituent polymers: cellulose and hemicellulose, which are both polysaccharides; and lignin, which is a polymer of phenyl propanoid sub-units. If these three polymers can be broken down into sugars or lignin monomers, multi-step biological and catalytic processes are then required to produce molecules identical to those currently derived from petroleum. In both depolymerization and catalytic upgrading, the biggest challenge is not achieving the desired reaction, but rather avoiding being outcompeted by other, detrimental reactions, such as degradation reactions, side reactions, or catalyst deactivation. These issues, along with the complexity of transforming natural structures to petroleum structures, has plagued the development of biobased chemicals.

In this talk, Jeremy Luterbacher will present several approaches to these challenges that my lab has developed, which notably preserve and build on these natural structures, rather than transforming them into petroleum-like replacements. I will show how we can use functionalization chemistry, both during lignin extraction and polysaccharide depolymerization, to reversibly ‘trap’ stabilized intermediate molecules, preserve their structure, and facilitate their high-yield upgrading. He will also discuss how targeted surface modifications on the heterogeneous catalysts associated with these transformations can lead to dramatic changes in activity, stability, and selectivity, even in the presence of highly oxygenated renewable streams. Finally, he will present how this same functionalization can be used to create new commodity chemicals, including polymers, that build new products around these preserved natural structures, as opposed to trying to replicate petroleum structures. He will highlight how the presence of these natural structures leads to molecules that are, by their very design, much easier to produce and more sustainable than current alternatives.