This section contains recommended exercises and information about the midterm and final test.
should absolutely NOT use 'arrow pushing', 'curved arrows', or 'curly
arrows' when working on organometallic problems in CH328.
- CH328 students regularly make the mistake of drawing structures where one or more carbons do not have the required four bonds. Check your work carefully to avoid this problem. In difficult cases, explicitly show the hydrogen atoms bonded to carbon, to ensure that you see all bonds.
- Typical organometallic problems and questions have a transition metal involved in the chemical reactions. Therefore, in CH328, ANY proposed reaction mechanism/explanation where the metal does NOT play a role would be wrong. In particular, no C-H bond can be cleaved other than via addition to a d-metal, except when the reaction involves a carbocation, R3C+, a carbanion, R3C-, or an electropositive metal alkyl, e.g., Mδ+-δ-CH3.
- Familiarize yourself with the properties of the typical ligands found in organometallic compounds. If you have any problem counting metal electrons and deciding metal oxidation states, talk to the instructor ASAP. Students experiencing these problems are at a particular risk of failing the course.
- Organometallic reactions involve a small number of mechanisms that are easy to learn and use. These include C-C and C-H bond forming reactions (insertions and reductive eliminations) and the C-H cleavage reactions (α- or β-H eliminations).
- On a test, when at a loss, do not
fantasize - there is no chance you would be able to 'invent' a mechanism
if you do not know organometallic chemistry. Offering nonsense or absurd responses to test questions may result in a penalty.
|2014||CH328 Test 1||Document|
|2014||CH328 Test 2||Document|
|2013||CH328 Final test||Document|