10. Addition Reactions

Provide a mechanism for the following reactions occurring with rearrangement.

(b)

Using an excess of HCl in the following reaction resulted in a product that was not simply the substitution of chlorine for the hydroxyl group. Predict the identity of the product obtained.

Provide an arrow-pushing mechanism that rationalizes the formation of each alkyl halide in Assessment 8.19.

Suggest an alkene that, upon reaction with the appropriate hydrohalic acid, will produce only the alkyl halide shown. [Ignore stereochemistry.]

(d)

Provide an arrow-pushing mechanism that rationalizes the formation of each of the products you predicted in Assessment 8.31. Make sure your mechanism accounts for all products formed, including stereoisomers and regioisomers, where applicable.

The following reaction gives two different constitutional isomers in nearly equal yields. Why doesn't this reaction produce only one product?

Which of the following alkenes would you expect to react fastest with HBr in each pair?

(b)

A wayward chemist proposed the following mechanism for the addition of HBr to an alkene.

(a) Why is this mechanism unlikely?

(b) Compare the reaction coordinate diagrams for the actual mechanism studied in Section 8.3.1 and this alternate mechanism on the same graph.

What is the expected product for the reaction of each of the following alkenes with (i) HBr and (ii) HCl?

(e)

a. Is the reaction of 2-butene with HBr regioselective?

b. Is it stereoselective?

c. Is it stereospecific?

What alkene should be used to synthesize each of the following alkyl bromides?

d.

Propose a mechanism for each of the following reactions:

b.

What is the major product obtained from the addition of HBr to the following compound?

Which of the following compounds reacts with HBr more rapidly?

Of the possible products shown for the following reaction, are there any that will not be formed?