This paper describes work from the Milstein group in which ruthenium catalysts with pincer ligands are used to depolymerize nylons by breaking the C-N bond and hydrogenating the resulting products to amines and alcohols. Waste plastic is a serious environmental concern that needs a solution. Organometallic chemists put significant effort into finding ways to convert monomers into polymers, and now we must figure out ways to do the reverse. Plastic recycling is somewhat problematic as mechanical recycling leads to plastics that are not as useful as the original material, so developing better ways to chemically recycle these materials is very important. This literature discussion guides students through this paper. While brief, the introduction to the big picture problem is excellent and will likely provide plenty of opportunity for discussion.
- Gain a better appreciation for the problem of waste plastic we are currently facing
- Use the Covalent Bond Classification method to classify and count electrons in several ruthenium species
- Interpret experimental data to draw conclusions about catalytic efficiency
- Examine a proposed mechanism for this catalytic hydrogenation
I will be using this literature discussion in my class for the first time in the fall of 2022. I anticipate giving the first 7 questions to students before class so they have an opportunity to answer them prior to our discussion. The remaining questions will be part of our discussion in class. I am anticipating that we will spend a significant amount of time talking about big picture issues related to this paper, so I purposefully did not dive too deep into the proposed mechanism. There is certainly room to mine more information out of the mechanism sections, both experimental and computational, and I may add to this depending on the timing that I observe in class.
The answers to the first seven questions will be submitted at the start of class and reviewed more for effort than for correctness. The live discussion part will be mostly accessed on participation in the discussion.