Students in a sophomore-level inorganic chemistry course were asked to read the paper “High-Pressure Synthesis and Characterization of the Alkali Diazenide Li2N2” (Angew. Chem. Int. Ed. 2012, 51, 1873-1875. DOI: 10.1002/anie.201108252) in preparation for a class discussion. For many students, this was a first exposure to reading the primary literature.
The original description of the synthesis of [RuH(NO3)(CO)2(PPh3)2 appears in Inorg. Chem. (Critchlow, P. B.; Robinson, S. D. Inorg. Chem. 1978, 17, 1896). There are eight possible structures for this octahedral isomer (including two sets of enantiomers). Students are shown one of the structures and asked to draw the remaining seven. The authors analyze the spectroscopic data obtained for the compound in order to determine which isomer formed. Unfortunately, there was an error in the analysis.
We have prepared a YouTube video demonstrating a visually accessible kinetic isotope effect in the Cr(VI) oxidation process, a reaction commonly encountered in introductory organic chemistry. The demo provides students with an opportunity to see an isotope effect and then understand how it can be used to provide mechanistic evidence for the identification of a rate-determining reaction step.
Maggie Geselbracht has a great fondness for compounds with too many nitrogen atoms next to each other. This is a collection of problem sets and class activites based on the structure, bonding, and spectroscopy of a number of such compounds, drawn from the recent literature.
My first computational collection
In this activity, students construct molecular orbital correlation diagrams for several species (H2, He2, HeH), in a semi-quantitative fashion using a ruler and a list of first ionization energies. All the MO schema are placed on a common energy scale, and the stability of each orbital is reported using "cm from the top of the paper" as the unit of energy.
In this paper by Andersen and Berg (J. Am. Chem. Soc., 1988, 110 (14), pp 4849–4850) the authors present magnetic measurements that refute the calculated ground state of an organometallic cobalt nitrosyl dimer. Students will learn about two physical techniques for measuring magnetism and will learn how magnetic measurements can be used to indicate paramagnetism versus diamagnetism.
This is a literature-based activity that focuses on a review I recently published as part of a thematic series on C-H activation.
The review highlights similarities between the newly discovered frustrated Lewis pairs and polarized metal-ligand multiple bonds. There are many ways to use the review, but the attached set of questions focuses on drawing analogies among seemingly diverse types of reactivity using frontier-molecular-orbital considerations.
This is the In Class Activity that I use to review the concepts of Lewis Dot Structures, LDS, (connectivity, resonance, formal charges, etc.) learned in General Chemistry and to introduce new ideas of resonance contributions to the character of the molecule. The question itself is apparently very simple, but the discussion that it produces can be quite rich and brings in both new and old ideas of LDS, providing both a good review and a good segue into advanced ideas of Lewis Dot Structures.
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.