Chemistry 331 - Fall 1996

Homework, Chapter 4 - Alkenes and Alkynes


McMurry, pp 137 - 140:

Problems 4.25-31, 33, 34, 36, 39, 40, 41, 43, 44, 45, 46, 47, 53, 54, 55


1. Write IUPAC names, including designation of stereochemistry where needed, for each of the following compounds:





2. When chlorine is added to an alkene in aqueous (water) solution, another major product besides the dichloro addition product is usually observed. For example, propene reacts with aqueous chlorine to form 1-chloro-2-propanol as the major product.
Write a mechanism that explains how this product forms.
Indicate how formation of this product relates to the Markovnikov rule.



3. Many alkenes undergo polymerization not only by free radical polymerization, but also by cationic polymerization. During World War 2, as a substitute for natural rubber, butyl rubber was made by cationic polymerization of isobutylene (2-methylpropene).
Write a chain reaction mechanism for cationic polymerization of isobutylene, using strong acid (H+) as initiator.
Explain why isobutylene would be particularly favorable for this type of reaction.