Submitted by Nancy Williams / Scripps College, Pitzer College, Claremont McKenna College on Tue, 08/28/2012 - 19:01
My Notes

This contains three parts: A "Pre-Read" section for students to read before coming to class, an in-class worksheet to be worked in groups, and instructor keys for the worksheet.

The purpose of this exercise is to familiarize and give practice with identifying major classes of reaction (oxidative addition, etc.) in an organometallic catalytic cycle. After this exercise, students should be able to do the same for a new catalytic cycle provided by the instructor on a homework set or exam.

This pre-supposes that students are familiar with electron counting and organic reaction types, but does not presume prior knowledge of organometallic reaction types.

In many textbooks, the distinction between mechanism (e.g., stepwise oxidative addition) and reaction class (oxidative addition) is not always clear. Students can identify reaction class simply by looking at reactants and products, whereas identifying mechanisms requires more advanced understanding of organometallic chemistry. Thus, this exercise focuses on the more basic skill, reaction class identification.

There is no universal set of terms or agreed upon classification of reactions in organometallic chemistry, so I have tried to create one here. Many, many other categorization schemes could be imagined, and some might be far superior. I would be eager for someone to take this and improve upon it to create their own exercise to resubmit to VIPEr.

Learning Goals

A student should be able to classify reactions in another such blank reaction scheme as they see in this worksheet at a later date. 

Equipment needs


Implementation Notes

I would give the Pre-Read to them the day before, telling them they should be ready to describe one of these cycles at the board in the next class. The next class period, I would then ask several volunteers to give a brief at-the-board summary of one of the reaction types (letting them use the pre-read as a crutch). Thereafter, I'd break into groups of 3-4, and let them work through the worksheet, followed by having them write up the cycles on the board (and writing out the molecules and cycles is a good exercise in itself) and talk through the decisions they made. 

Time Required
ca. 50 minutes


Evaluation Methods

Haven't done it, but I'd pick a (pretty easy) catalytic cycle, put it in the same format with spaces for bubble answers, and see whether they could do the same on their own with a system they hadn't done this before with.

Evaluation Results

None yet.

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Laurel Goj Habgood / Rollins College

My students really appreciated the detailed pre-read.

Sun, 10/30/2016 - 16:02 Permalink
Brad Wile / Ohio Northern University

This is a fantastic way to present this material. I agree wholeheartedly with the idea that ligand association/dissociation is "item 0!" I struggle with how to frame some of these for students at the foundation level, since I don't like how most textbooks at this level classify the transformations of OM complexes. Do you discuss "attack on coordinated ligands" at all in this context? I'm totally going to use this as a basis for my future in-class discussion with the foundation class!

Thu, 06/25/2020 - 16:06 Permalink