Chem 336 - Spring 2000
Organic Chemistry III
Dr. Carl C. Wamser

Chapter 19 Puzzler

In 1900 Moses Gomberg (U. Michigan) tried to make hexaphenylethane.

2 Ph3C-CI + Zn ---> Ph3C-CPh3 + ZnCl2

The properties were unusual, however, and he postulated free radicals.

Ph3C-CPh3 <=====> 2 Ph3C*

1) To how many sites (different carbon atoms) can the radical be delocalized by resonance?
2) How many total resonance forms?
3) What properties do you think made him suspicious of hexaphenylethane?