Resolution of Werner complexes -- the COVID edition

Submitted by Adam Johnson / Harvey Mudd College on Fri, 02/05/2021 - 12:44
Description

This is a classic experiment that has been revised and updated numerous times over the years. The experiment can be found in Girolami, Rauchfuss and Angelici, 3rd edition, but that edition removed some purification steps that were present in the earlier edition which has plagued generations of my students with poor resolution of the enantiomers. Marion Cass published a J. Chem. Educ. article in 2015 that included a pH determination and added back in the recrystallization step. This allowed my students to achieve higher yields and greater resolution in Spring 2020.

metal acac complexes the COVID 19 version

Submitted by Adam Johnson / Harvey Mudd College on Mon, 01/18/2021 - 16:56
Description

For our virtual offering of inorganic chemistry laboratory at Harvey Mudd College in Spring 2021, I made some videos and collected some high quality data (IR, 1H NMR, MS, UV-Vis, mp, and X-ray diffraction) that I will make available for my students. The videos show the synthesis of Co and Mn acacs, the difference between as-prepared and recrystallized compounds, making solutions for UV-Vis and Evans method NMR, and making Evans method capillary tubes. The procedures for the synthesis of these compounds is found in Woolins (either the first or second editions). 

SLiThEr #7: Assessment Using Literature Discussions

Submitted by Kyle Grice / DePaul University on Tue, 12/29/2020 - 17:55
Description

This is the seventh SLiThEr () in the series. In this presentation/discussion, Dr. Shirley Lin explains how she used a literature discussion with students to assess their learning and knowledge. This was for a upper-division senior seminar course. In particular, she discusses questions at various levels of Bloom's Taxonomy. She also explains how to use concepts from Chemical Education Research to really dig down and assess student knowledge. 

SLiThEr #1: Creating online inorganic chemistry labs

Submitted by Kyle Grice / DePaul University on Tue, 12/29/2020 - 14:29
Description

This is the link to the first SLiThEr (Supporting Learning with Interactive Teaching: a Hosted, Engaging Roundtable), presented by Kyle Grice and Hosted by Chip Nataro. The SLiThEr was recorded and posted on YouTube (see the web resources link). 

Synthesis of Fluorescent Aluminum Complexes

Submitted by Taylor Haynes / California Polytechnic, San Luis Obispo on Fri, 08/28/2020 - 15:34
Description

In this experiment, Students synthesize a Schiff Base and the corresponding aluminum complex to measure fluorescence. The lab provides exposure to air-free synthetic techniques, including the use of Schlenk Line techniques and safe handling of sure-seal bottles. Following data collection, students will be able to explain fluorescence spectroscopy and compare it to absorbance spectroscopy.

A cobalt hydroformylation catalyst tribute to Malcolm Green

Submitted by Chip Nataro / Lafayette College on Mon, 07/27/2020 - 20:00
Description

In this paper (Llewellyn, Green and Cowley, Dalton Trans. 2006, 4164-4168) the synthesis and characterization of two cobalt compounds with an N-heterocyclic carbene ligand (IMes) are reported. the first, [Co(CO)3(IMes)Me] was prepared by the reaction of [Co(CO)3(PPh3)Me] with IMes. The second compound, [Co(CO)3(IMes)COMe] is formed by the addition of Co to the first.

A copper "Click" catalyst for the synthesis of 1,2,3-triazoles

Submitted by Chip Nataro / Lafayette College on Wed, 06/10/2020 - 11:40
Description

This paper (Gayen, F.R.; Ali, A.A.; Bora, D.; Roy, S.; Saha, S.; Saikia, L.; Goswamee, R.L. and Saha, B. Dalton Trans2020, 49, 6578) describes the synthesis, characterization and catalytic activity of a copper complex with a ferrocene-containing Schiff base ligand. The article is relatively short but packed with information. However, many of the details that are assumed knowledge in the article make for wonderful questions some of which I hope I have captured.

Gold carbonyl complexes

Submitted by Adam Johnson / Harvey Mudd College on Tue, 06/09/2020 - 15:06
Description

I've been meaning to write an LO on non-classical metal carbonyl complexes for a long time. This paper describes the synthesis and characterization of a gold carbonyl prepared in superacidic media. The LO asks the students to do some relatively straightforward reduced mass calculations to predict the 13C labeled CO stretch from the unlabeled one, but then asks the students to think about /why/ the Au-CO stretch is /higher/ than that of free CO.

Migratory Insertion Guided inquiry

Submitted by Adam Johnson / Harvey Mudd College on Mon, 04/06/2020 - 12:43
Description

The migratory insertion reaction is one of the "four" main reactions in organometallic chemistry. It involves the formation of an acyl group by insertion of a CO molecule into a metal alkyl bond. The reaction is sometimes called the carbonyl insertion reaction because the product appears to be a result of direct insertion of the CO into the metal alkyl, but that name implies a mechanistic pathway that may not be in operation.

chromium and molybdenum arene complexes (COVID-19 version)

Submitted by Adam Johnson / Harvey Mudd College on Sat, 03/21/2020 - 19:49
Description

April 2021 update: I am in the process of expanding this laboratory and have now recorded videos, linked below, on youtube. There is a video of general air sensitive reaction setup, the synthesis and isolation of the mesitylene and the N,N-diethylaniline derivatives. I also have better quality data which I will add here as well.