11 Jan 2016

Synthesis and Characterization of a Series of Organometallic Ru(II) Complexes with Fluorinated Phosphine and Phosphite Ligands

Lab Experiment

Submitted by John Lee, University of Tennessee Chattanooga
Categories
Description: 

In this experiment, students will synthesize and characterize a series of Ru(II) p-cymene piano-stool complexes. Each complex will contain p-cymene as the "seat" and two chloride donors in addition to a phosphine or phosphite with varying amounts of fluorine, which together serve as the "stands". There are a total of four phosphine ligands and three phosphites, which include triphenylphosphine and trimethylphosphite that do not contain any fluorine. This experiment combines complex synthesis, characterization, data analysis and data sharing.

AttachmentSize
File Student Handout48.21 KB
Learning Goals: 

A student should be able to:

  1. Prepare a series of Ru(II) phosphine and phosphite complexes
  2. Characterize the complexes by multi-nuclear NMR spectroscopy
  3. Characterize the complexes by UV-vis spectroscopy
  4. Analyze structural data in Mercury
  5. Use physical characterization data to formulate trends
  6. Use data tables when appropriate
  7. Express conclusions
  8. Write a full ACS journal style lab report 
Equipment needs: 

Standard laboratory equipment/glassware

Rotary evaporator

FT-NMR with multinuclear capablity 

UV-vis spectrophotometer

Implementation Notes: 

This experiment will be piloted during the 2016-2017 school year. If others in the VIPEr community try this experiment please post your comments and/or consider filling out the feedback file attached and sending to john-lee@utc.edu

Students will synthesize and characterize one compound each, and should share spectral and other characterization data in order to perform a complete study for their report. All complexes are air-stable and can be prepared without the need for anaerobic techniques. Students should form a hypothesis on the donor ability of the ligand and then use their characterization data along with the structure of the phosphine or phosphite to support and/or refine their original predictions.

Time Required: 
Two to Three 3-hour lab periods
Evaluation
Evaluation Methods: 

When implemented during the 2016-2017 school year a formal lab report will be required. However, other suitable methods would include, but are not limited to an oral presentation or a lab memo.

Evaluation Results: 

The experiment described herein will be piloted during the 2016-2017 school year. However, all complexes have been prepared by undergraduate students/researchers at all levels during the completion of the original project. 

Creative Commons License: 
Creative Commons Licence

Comments

This experiment, though not implemented in a teaching lab yet, has been successfully completed by undergraduate students in the research lab. It is my hope that this learning object will provide a useful organometallic/coordination chemistry experiment. And, those who implement will take advantage of Sheila Smith's recent BITeS blog on "Crowdsourcing Assessment Data" in order to further help turn this into an excellent and adaptable inorganic lab experiment.

John, I'm going to be trying this with my very small class this term.  I may be hitting you up for advice and help

This looks really cool. A couple of questions/comments - the link on this page to the web resource is broken. Would these be amenable to analysis by CV? I'm looking for labs that incorporate more electrochemistry. Thanks!

Should be CV-amenable... the Ru(II/III) couple should move...  I'd be interested in trying this next time I teach.

Thank you for all the feedback, and I apologize for not responding earlier. Sheila, glad you were able to use the experiment and I hope it worked. Vanessa and Kyle, yes you should be able to see the Ru(III/II) couple and indeed it should move. At the time we did not have electrochemical equipment available (coming soon though!) but please feel free to see what you find. All the complexes are soluble in acetonitrile.

It looks like the link is doubled on doi.org. Here it is:

https://doi.org/10.1080/00958972.2015.1114613

 

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