VIPEr

Subdiscipline:

f-block Chemistry

Science Skills, Practices, and Resources

Course Level:

First year

Second year

Bonding models: Discrete molecules

Equipment needs:

Computer for each student with ChemDraw installed.

Topics Covered:

Communication skills

Molecular structure

Professional skills development

Visualization

Prerequisites:

No Prerequisites

First Semester Inorganic Chemistry / Foundation Course in Inorganic Chemistry

Literature Introduction to Coordination Complexes

Related activities:

Catalytic cycles and artistry: Chalk Drawing 101

Implementation Notes:

This was implemented in a 24-student course in the week following an introduction to basic ChemDraw use. Students were shown the techniques in lecture format using the attached Powerpoint presentation. After the presentation, students had access to the slides and could refer to them while completing the activity.

In-class most students were mostly able to complete the worksheet using the powerpoint slides as a guide. However, the instructor also walked around to give individual tips and instruction.

The total time for the activity and lecture was 1 hour 50 min, but it could be shortened or assigned for homework.

In the section where students are asked to interpret molecular formulas, this is done ignoring ligand abbreviations, such as R groups or simplifications of chelating ligands. This could be left off, however it was a useful way to introduce students to drawing simplifications they may find in the literature. Most students just interpreted the formula based on what was drawn, and some students looked up the original papers to get a more accurate formula (although this takes much more time).

Time Required:

60-110 min

Web Resources:

Paper1: Improved Synthesis of [CpRRhCl2]2 Complexes

Paper 2: Photoluminescence of Cyclometalated Iridium Complexes in Poly(methyl methacrylate) Films

Paper 3: Structure, Magnetism, and Multi-electron Reduction Reactivity of the Inverse Sandwich Reduced Arene La2+ Complex [{[C5H

Paper 4: Synthesis and Reactivity of Cp*IrIII Complexes with a C−S Chelate Displaying Metal/Sulfur Bifunctionality

Paper 5: Copper-Catalyzed Synthesis of β‐Azido Sulfonates or Fluorinated Alkanes: Divergent Reactivity of Sodium Sulfinates

Paper 6: Exclusive Csp3−Csp3 vs Csp2−Csp3 Reductive Elimination from PtIV Governed by Ligand Constraints

Paper 7: Intermolecular Radical Mediated Anti-Markovnikov Alkene Hydroamination Using N‐Hydroxyphthalimide

31 Jan 2019

More Electron Counting and CBC Assignments for Organometallic Complexes

Submitted by Matt Whited, Carleton College

Evaluation Methods:

Students were evaluated informally as I walked around to help the groups as well as during presentations.

Evaluation Results:

A large majority of the students had no problem making assignments for the simple and intermediate cases. This outcome is largely a testament to the ease of use of the CBC method. In fact, students who had no background in inorganic or organometallic chemistry tended to perform a little better because they were less likely to bring in preconceptions about "oxidation state".

Students struggled a bit with the Z-type Ga ligand, which is great because it helped them move forward in understanding the periodic relationship to Al and B. Students also struggled a bit with the cyclic (alkyl)aminocarbene ligands in the cobalt dimer, since they had not seen those before.

Description:

This in-class group activity extends my original post by providing more examples of varying difficulty for students to assign MLXZ classifications and electron counts to organometallic complexes. The answers to these are unambiguous within the CBC system, but they provide excellent starting points for conversation with students about bonding formalisms with organometallics.

Learning Goals:

* Students should be able to use the covalent bond classification method to assign MLXZ classifications to a variety of organometallic complexes.

* Students should be able to defend their assignments using both organic and inorganic views of structure and bonding.

* Students will understand the ambiguities associated with assigning bond orders, valencies, oxidation states, etc., with the hope that their understanding of covalently bonded organometallic systems will become more nuanced.

Subdiscipline:

Prerequisites:

Course Level:

Bonding models: Discrete molecules

Topics Covered:

Corequisites:

Electron Counting and CBC Assignments for Organometallic Complexes

Related activities:

CBC (Covalent Bond Classification) Method of Electron Counting

The Covalent Bond Classification (CBC) website

Implementation Notes:

I split students into groups of 3, as noted in the handout. Since this was a small class, I used 10 problems (all 7 from this handout and 3 from the earlier activity) and each student presented one answer. Students took about 25 minutes to work through the problems, and then I had the students present and encouraged questions and challenges to their assignments. The students brought several interesting insights that deepened their understanding of bonding and the connection between Organic Chemistry (which they have all taken) and Inorganic/Organometallic Chemistry (which most of them have not seen).

Time Required:

45 minutes

Web Resources:

CBC Paper in J Chem Educ

31 Jan 2019

5-ish Slides About Bridging Hydrides and the [Cr(CO)5HCr(CO)5] anion

Submitted by Kyle Grice, DePaul University

Description:

This set of slides was made for my Organometallics class based on questions about bridging hydrides and specifically the chromium molecule. I decided to make these slides to answer the questions, and do a DFT calc to show the MO's involved in bonding of the hydride.

Topics Covered:

Bonding models: Discrete molecules

Computer modeling

Electronic structure

First Semester Inorganic Chemistry / Foundation Course in Inorganic Chemistry

Symmetry

Visualization

Prerequisites:

Course Level:

Second year

Corequisites:

Subdiscipline:

Literature Discussion of R3CH→ SiFR3 Agostic Interactions

Learning Goals:

A student will be able to explain bridging hydride bonding

A student will be able to perform electron counting on a chromium comples with a bridging hydride

A student will be able to interepret calculated DFT molecular orbitals.

Related activities:

Introduction to Agostic Interactions

Molecular Orbitals of Square-Planar Tetrahydrides

Time Required:

15 min

Evaluation

Evaluation Methods:

This was provided as supplementary material outside of lecture.

29 Jan 2019

Inorganic Chemistry

Submitted by James F. Dunne, Central College

28 Jan 2019

Guided Literature Discussion of “Next-Generation Water-Soluble Homogeneous Catalysts for Conversion of Glycerol to Lactic Acid”

Submitted by Murielle Watzky, University of Northern Colorado

Evaluation Methods:

Concepts covered during literature discussions will be included among exam materials.

Evaluation Results:

N/A

Description:

This Guided Literature Discussion was assigned as a course project, and is the result of work originated by students Joie Games and Benjamin Melzer. It is based on the article “Next-Generation Water-Soluble Homogeneous Catalysts for Conversion of Glycerol to Lactic Acid” by Matthew Finn, J. August Ridenour, Jacob Heltzel, Christopher Cahill, and Adelina Voutchkova-Kostal in Organometallics 2018 37 (9), 1400-1409. It includes a Reading Guide that will direct students to specific sections of the paper that were emphasized in the discussion. This article reports a systematic study of a series of homogeneous catalysts for the conversion of glycerol to lactic acid.

Course Level:

First Semester Inorganic Chemistry / Foundation Course in Inorganic Chemistry

Prerequisites:

Corequisites:

Subdiscipline:

Learning Goals:

After reading and discussing this article, a student should be able to…

- Apply the CBC electron-counting method to homogeneous catalysts.

- Understand the effect of metal and/or metal oxidation state on catalyst activity.

- Understand the effect of ligand and/or ligand charge on catalyst activity.

- Understand the differences between microwave and conventional heating.

Topics Covered:

Catalysis

Molecular structure

Physical methods / analytical techniques

Reaction mechanisms

Synthesis and reactivity

Related activities:

Guiding questions for: Redox-Controlled Polymerization of Lactide Catalyzed by Bis(imino)pyridine Iron Bis(alkoxide) Complexes

Iron Catalysts for Lactide Polymerization

Implementation Notes:

I am planning on assigning this LO as a graded in-class group discussion. Students will be given a copy of the article, reading guide, and discussion questions one week in advance. On the day of the discussion, students will be assigned in groups of 2-3. They will then have one lecture period to answer the questions in writing as a group. A portion of their grade (20%) is dedicated to literature discussions (4-6 over the course of the semester). The grading rubric involves 3 possible ratings for each question/answer: “excellent”, “acceptable”, or “needs work”. [This article is among the free-access ACS Editors’ Choice.]

Time Required:

1 lecture period, with materials given one week in advance

Web Resources:

Next-Generation Water-Soluble Homogeneous Catalysts for Conversion of Glycerol to Lactic Acid

28 Jan 2019

Guided Literature Discussion of “Deca-Arylsamarocene: An Unusually Inert Sm(II) Sandwich Complex”

Submitted by Murielle Watzky, University of Northern Colorado

Evaluation Methods:

A portion of their grade (20%) is dedicated to literature discussions (4-6 over the course of the semester). The grading rubric involves 3 possible ratings for each question/answer: “excellent”, “acceptable”, or “needs work”.

Concepts covered during literature discussions will be included among exam materials.

Evaluation Results:

N/A

Description:

This Guided Literature Discussion was assigned as a course project, and is the result of work originated by students Christopher Lasterand Patrick Wilson. It is based on the article “Deca-Arylsamarocene: An Unusually Inert Sm(II) Sandwich Complex” by Niels J. C. van Velzen and Sjoerd Harder in Organometallics 2018, 37, 2263−2271. It includes a Reading Guide that will direct students to specific sections of the paper that were emphasized in the discussion. This article presents a study of the reactivity of bulky Cp^Ar-Et/iPr₂Sm complexes that is contrasted to the more well-known Cp*₂Sm.

Course Level:

First Semester Inorganic Chemistry / Foundation Course in Inorganic Chemistry

Prerequisites:

Corequisites:

Subdiscipline:

f-block Chemistry

Spectroscopy and Structural Methods

Learning Goals:

After reading and discussing this article, a student should be able to…

- Be more familiar with the chemistry of sandwich samarocene complexes.

- Understand how bulky ligands affect structure and reactivity in a sandwich complex.

- Apply the CBC method to identify ligand functions and metal valence number/ligand bond number.

- Understand how XRD bond distances can help determine a ligand charge.

Topics Covered:

Physical methods / analytical techniques

Synthesis and reactivity

Related activities:

Guided Literature Discussion of “Synthesis, Electrochemistry, and Reactivity of Half-Sandwich Ruthenium Complexes Bearing Metallocene-Based Bisphosphines”

Binding dinitrogen to titanium sandwich compounds

Implementation Notes:

I am planning on assigning this LO as a graded in-class group discussion. Students will be given a copy of the article, reading guide, and discussion questions one week in advance. On the day of the discussion, students will be assigned in groups of 2-3. They will then have one lecture period to answer the questions in writing as a group. [This article is among the free-access ACS Editors’ Choice.]

Time Required:

1 lecture period, with materials given one week in advance

Web Resources:

Deca-Arylsamarocene: An Unusually Inert Sm(II) Sandwich Complex

28 Jan 2019

Inorganic Chemistry

Submitted by Kari Young, Centre College

16 Jan 2019

Guided Literature Discussion of “Mechanism of the Platinum(II)-Catalyzed Hydroamination of 4-Pentenylamines”

Submitted by Murielle Watzky, University of Northern Colorado

Evaluation Methods:

Concepts covered during literature discussions will be included among exam materials.

Evaluation Results:

N/A

Description:

This Guided Literature Discussion was assigned as a course project, and is the result of work originated by students Jana Forster and Kristofer Reiser. It is based on the article “Mechanism of the Platinum(II)-Catalyzed Hydroamination of 4-Pentenylamines” by Christopher F. Bender, Timothy J. Brown, and Ross A. Widenhoefer in Organometallics 2016 35 (2), 113-125. It includes a Reading Guide that will direct students to specific sections of the paper that were emphasized in the discussion. This article presents a mechanistic study of hydroamination reactions catalyzed by a late transition metal complex.

Course Level:

First Semester Inorganic Chemistry / Foundation Course in Inorganic Chemistry

Prerequisites:

Corequisites:

Subdiscipline:

Spectroscopy and Structural Methods

Learning Goals:

After reading and discussing this article, a student should be able to…

- Apply the CBC electron-counting method.

- Understand how ³¹P {¹H} NMR can help differentiate intermediates.

- Use information provided by Eyring plots.

- Understand how a catalyst resting state and turnover-limiting step can be identified.

- Understand the role of kinetics in mechanistic investigations.

- Appreciate how proposed reaction mechanisms can be evaluated.

Topics Covered:

Kinetics

Molecular structure