Synthesis and Characterization of Novel Molybdenum(II) Piano-Stool Complexes to change the title use the 'Full Editing Tools' option on the right

Chem 352: Laboratory in Advanced Inorganic Chemistry
Number of Students in Class: 14

In spring 2012 and based on previous work by Prof. Gretchen Hofmeister, I began extending a laboratory experience for students in Chem 352 to have them make variants of a known organometallic product as part of the lab. In short, the migratory insertion of a carbonyl group (a common organometallic transformation) into a molybdenum–methyl bond upon addition of triphenylphosphine had been well established by the literature and previous experiments in Chem 352. We proposed last year that a similar transformation would be observed upon minor modification of the phosphine (from triphenyl- to methyldiphenylphosphine), and the reaction was successful as expected. In addition to publication of our crystallographic results in a peer-reviewed journal, there were several welcome outcomes of this project with respect to student learning, the most important being that students developed skills in (a) making "on-the-fly" modifications to reported synthetic procedures, (b) predicting, interpreting, and rationalizing data collected for previously unreported complexes, and (c) recognizing and making hypotheses about unexpected side reactions and byproducts that can result in a new synthesis.

I now wish to extend these preliminary findings to a wider variety of phosphine ligand complexes, most of which have not been previously reported (and none of which have been fully characterized). This will allow the experiment to take the form of an independent project where students can pool results and test hypotheses, most specifically regarding the impact of phosphine substitution patterns (e.g., introduction of a hydrogen-bonding group, switching from a tertiary to a secondary phosphine) on solid-state and solution behavior. Parts of this new approach will be implemented starting in spring 2013 using ligands already on hand in the chemistry department and the Whited research lab. The specific learning outcomes that I hope to see (in addition to overarching goals about attitudes toward research, confidence making/testing hypotheses, etc.) are the three listed at the end of the previous paragraph.

I am requesting two weeks of support in the form of a curriculum development stipend for summer 2013 to focus on the following areas:
* Expansion of several aspects that have already been studied, analysis of the data from spring 2012/2013, selection and synthesis of new phosphine (and possibly other) ligands to use in spring 2014 and beyond.
* Exploration of several possible kinetics experiments that were suggested by unexpected findings the last time around.
* Modifying the requirements of the lab report and lab notebook graded portions of the experiments to encourage students to make hypotheses, search the literature, and interpret their data independently as well as pooling results with other groups.
* Compilation of crystallographic data from spring 2013 for a second publication from the lab (I hope that peer-reviewed publications from this curricular lab will become a regular feature, but some modification will be necessary for that to be sustainable).
* Writing up several years worth of findings from this experiment and Prof. Hofmeister's original version for a J Chem Ed article and for sharing with the inorganic community on the Virtual Inorganic Pedagogical Resource website (for which I am an administrator).

Aside from the assessment resources I plan to develop that will contribute to the students' grades (see above), I will be using the CURE survey to assess the impact of this lab on students' attitudes toward research and confidence in approaching previously unexplored problems.

* demonstrate comfort proposing and carrying out new chemical reactions based on known templates, including making "on-the-fly" modifications to known procedures
* make predictions about the spectroscopic properties of new inorganic compounds
* recognize and make hypotheses about unexpected side reactions and byproducts in chemical synthesis
* learn about the technique of X-ray crystallography and gain insights into aspects of the peer-reviewed