CHEM 125A - Freshman Organic Chemistry I
Lecture 22 - Radical and Type Theories (1832-1850). Work by Wohler and Liebig on benzaldehyde inspired a general theory of organic chemistry focusing on so-called radicals, collections of atoms which appeared to behave as elements and persist unchanged through organic reactions. Liebig's French rival, Dumas, temporarily advocated radicals, but converted to the competing theory of types which could accommodate substitution reactions. These decades teach more about the psychology, sociology, and short-sightedness of leading chemists than about fundamental chemistry, but both theories survive in competing schemes of modern organic nomenclature. The HOMO-LUMO mechanism of addition to alkenes and the SOMO mechanism of free-radical chain reactions are introduced. (from oyc.yale.edu)
| Lecture 22 - Radical and Type Theories (1832-1850) |
| Time | Lecture Chapters |
| [00:00:00] | 1. Benzaldehyde and the Focus on Radicals |
| [00:12:52] | 2. Dumas's "Note on the Present State of Organic Chemistry" |
| [00:21:39] | 3. The Mystery of the Chlorinated Candle |
| [00:35:00] | 4. Further Development of the Law of Substitution and the Theory of Types |
| [00:47:36] | 5. Kolbe and the First Free Methyl Radical |
| References |
| Lecture 22 - Radical and Type Theories (1832-1850) Instructor: Professor J. Michael McBride. Resources: Professor McBride's website resource for CHEM 125 (Fall 2008). Transcript [html]. Audio [mp3]. Download Video [mov]. |
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