Draw a mechanism for the acid-catalyzed, nonenzymatic conversion of DPP to IPP. How do you know your mechanism is correct?

A chemist unsuccessfully attempted to produce the 1,4-cyclohexanediol by hydration of the cyclohexene shown.

(a) Provide a mechanism for the formation of the actual product.

(b) Suggest a pathway using acetyl chloride as a protecting group that will allow for the formation of the desired product.

The acid-catalyzed dehydration we learned in this chapter is reversible, as shown below.

(d) How might you shift the equilibrium to the right?

When combining isoprene equivalents, IPP is never the electrophile. Why might this be? What is special about DPP that allows it to function better as an electrophile? [Draw the carbocation that each becomes.]

Suggest a mechanism for the synthesis of farnesol beginning with IPP and DPP.

Provide the expected product for the reaction of each of the following alkenes with H₂SO₄ and H₂O.

(b)

The acid-catalyzed dehydration we learned in this chapter is reversible, as shown below.

(b) Without looking back, how do you know this mechanism is correct?

The pK_a values of the carboxylic acid groups of oxaloacetic acid are 2.22 and 3.98.

b. The amount of hydrate present in an aqueous solution of oxaloacetic acid depends on the pH of the solution: 95% at pH 0, 81% at pH 1.3, 35% at pH 3.1, 13% at pH 4.7, 6% at pH 6.7, and 6% at pH 12.7. Explain this pH dependence.

How could the following compounds be prepared using an alkene as one of the starting materials?

c.