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Catalysts from the 2005 Nobel Prize
in Chemistry
The 2005 Nobel Prize for Chemistry celebrated molecules that
are of great value to researchers, to the broader society,
and to chemical educators. The work of Chauvin, Grubbs, and
Schrock, and their many collaborators, is described by Charles
P. Casey, and an experiment using the second generation
Grubbs catalyst has been developed by Douglass
Taber and Kevin Frankowski.
The molecules themselves serve as useful examples of the
utility of 3-dimensional structures in the classroom and laboratory,
and on assignments and exams. Comparison of the interactive
structures of the first generation Grubbs catalyst with the
structure in the Casey paper helps beginning students to develop
their skills at reading chemical structure shorthand in a
way that is of great value when studying reaction mechanisms,
spectroscopy, or almost any other aspect of chemistry or any
of the molecular sciences—size and shape do matter.
The 2-dimensional form of the structure might easily give
students the impression that the ruthenium is quite open in
this molecule, but they quickly see that this is clearly not
the case when they examine the 3-dimensional form. Students
who have done this are unlikely to be surprised to learn that
the catalyst is activated by dissociation of one of the tricyclohexylphosphine
groups.
In introductory courses it is too often the case that the
discussion of metal complexes focuses on classic Werner species
(with, perhaps, some discussion of hemoglobin/myoglobin).
Such complexes are indeed useful icons for introducing ideas
of color, spectra, and magnetic properties arising from the
lowering of the degeneracy of the d-orbitals on the metal.
However, students should also be exposed to the role of metal
complexes in catalysis, and the molecules for this month are
excellent examples for classroom use.
The Casey paper ends with a quote on the continuing need
to support basic research. Students, whether or not they become
scientists, will become taxpayer and, in some cases, decision
makers. They need constantly to be reminded that individual
molecules are important to our daily lives and to the functioning
of society. These catalysts are useful entrees to such discussion.
Viewing Requirements
In addition to the static images, two fully manipulable versions
(Jmol, MDLChime)
of these molecules appear below.
 Download
Chime (registration required)
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