Illustrating catalysis with interlocking building blocks: Correlation between structure of a metallocene catalyst and the stereoregularity of polypropylene
Ryo Horikoshi, Yoji Kobayashi, Hiroshi Kageyama. Journal of Chemical Education, 2013, 90, 620-622.
Catalysis with transition-metal complexes is a part of the inorganic
chemistry curriculum and a challenging topic for upper-level
undergraduate and graduate students. A hands-on teaching aid has been
developed for use during conventional lectures to help students
understand these catalytic reactions. A unique method of illustrating
the coordination polymerization of propylene with interlocking building
blocks is described. Three metallocene block models mimicking real
catalysts recognize top and bottom faces of a prochiral propylene
monomer block model and subsequently provide three polypropylene
structures with different tacticity. The monomer recognition processes
of the metallocene block models are based on steric hindrance, similar
to those of the real catalysts.