25. Models in 3D Space (1869-1877); Optical Isomers

Freshman Organic Chemistry (CHEM 125)

Despite cautions from their conservative elders, young chemists like Paternó and van't Hoff began interpreting molecular graphs in terms of the arrangement of a molecule's atoms in 3-dimensional space. Benzene was one such case, but still more significant was the prediction, based on puzzling isomerism involving "optical activity," that molecules could be "chiral," that is, right- or left-handed. Louis Pasteur effected the first artificial separation of racemic acid into tartaric acid and its mirror-image.

00:00 - Chapter 1. Venturing into 3-D Arrangements of a Molecule's Atoms
11:41 - Chapter 2. Exchanges between van't Hoff and Ladenburg on Aromaticity and Chirality
22:58 - Chapter 3. In-Class Observations and Experiments on Chirality
39:14 - Chapter 4. Louis Pasteur's Artificial Separation of Racemic Acid

Complete course materials are available at the Open Yale Courses website: http://open.yale.edu/courses

This course was recorded in Fall 2008.