Lecture 27: Communicating Molecular Structure in Diagrams and Words
Lecture Details :
Freshman Organic Chemistry (CHEM 125)
It is important that chemists agree on notation and nomenclature in order to communicate molecular constitution and configuration. It is best when a diagram is as faithful as possible to the 3-dimensional shape of a molecule, but the conventional Fischer projection, which has been indispensable in understanding sugar configurations for over a century, involves highly distorted bonds. Ambiguity in diagrams or words has led to multibillion-dollar patent disputes involving popular drugs. International agreements provide descriptive, unambiguous, unique, systematic "IUPAC" names that are reasonably convenient for most organic molecules of modest molecular weight.
00:00 - Chapter 1. The Development of the Fischer Projections
16:27 - Chapter 2. Diastereomers and Enantiomers in van't Hoff's Brochure
23:14 - Chapter 3. Notation Ambiguities and Multibillion Dollar Pharmaceutical Disputes
39:26 - Chapter 4. The IUPAC and the Standardization of Molecular Nomenclature
Complete course materials are available at the Open Yale Courses website: http://open.yale.edu/courses
This course was recorded in Fall 2008.
Course Description :
How Do You Know - Force Laws, Lewis Structures and Resonance - Double Minima, Earnshaws Theorem and Plum - Puddings - Coping with Smallness and Scanning Probe Microscopy - X-Ray Diffraction-Seeing Bonds by Electron Difference Density - Quantum Mechanical Kinetic Energy - One-Dimensional Wave Functions - Chladni Figures and One - Electron Atoms - Reality and the Orbital Approximation - Orbital Correction and Plum - Pudding Molecules - Overlap and Atom - Pair Bonds - Overlap and Energy - Match - Checking Hybridization Theory with XH_3-Chemical Reactivity: SOMO, HOMO, and LUMO - Recognizing Functional Groups - Reaction Analogies and Carbonyl Reactivity - Amide, Carboxylic Acid and Alkyl Lithium-Oxygen and the Chemical Revolution - Rise of the Atomic Theory - Berzelius to Liebig and W�hler - Radical and Type Theories (1832-1850)-Valence Theory and Constitutional Structure (1858) - Determining Chemical Structure by Isomer Counting (1869)
Models in 3D Space (1869-1877); Optical Isomers - Vant Hoffs Tetrahedral Carbon and ChiralityCommunicating Molecular Structure in Diagrams and Words - Stereochemical Nomenclature; Racemization and Resolution - Preparing Single Enantiomers and the Mechanism of Optical Rotation - Esomeprazole as an Example of Drug Testing and Usage - Preparing Single Enantiomers and Conformational Energy - Stereotopicity and Baeyer Strain Theory -Conformational Energy and Molecular Mechanics - Sharpless Oxidation Catalysts and the Conformation of Cycloalkanes - Understanding Molecular Structure and Energy through Standard Bonds - Bond Energies, the Boltzmann Factor and Entropy - Potential Energy Surfaces, Transition State Theory and Reaction Mechanism