Do the five problems in the Alkane module of ORGO for practice. Work out the problem

BEFORE looking at the answer. [http://www.yale.edu/chem220/studyaids/index]

1) Show the initiation and propagation steps in the free radical chlorination of cyclohexane.

Calculate the heat of reaction of each significant step and for the overall reaction. Draw a reaction

profile for the process that includes the values you calculated. Make sure your diagram

is in accord with the Hammond Postulate.

2) How many different types of C-H bonds are present in cyclohexene? Which type has the

lowest BDE? Why? What is the major free radical monobromination product of cyclohexene? [pg.

165]

3) How many different monochlorination products can be formed in the free radical

chlorination of 2,3-dimethylbutane? What percentage of each is formed?

4) Draw methyl and t-butyl carbocations. Why is the second cation more stable than the

former?

5) The resonance stabilized carbanion on the top of page 167 is planar. Draw the conjugate

acid (acetaldehyde) of the carbanion such that one of the C-H bonds is aligned with the

C=O p-bond. Are the three C-H bonds equivalent? Explain which H of the methyl group

is the most acidic.