Assessment 8.74 revealed that oxymercuration could be used to make cyclic esters. Suggest a likely mechanism for this transformation.

Predict the product of the following aldehyde/ketone syntheses.

(d)

Would you expect the following to produce an equal or unequal mixture of stereoisomers?

(c)

Predict the product of each of the following alcohol synthesis reactions.

(a)

In 1973, Caine and Tuller reported a synthesis of racemic oplapanone, a sesquiterpene isolated from Oplopanax japonicus (a deciduous shrub) involving a reaction we learned in this chapter. Predict the product of the reaction shown. (Caine, D.; Tuller, F. N. J. Org. Chem. 1973, 38, 3663.)

Oxymercuration–reduction, like acid-catalyzed hydration, can be modified to synthesize ethers. Suggest an alkene and the appropriate reaction conditions to synthesize the following ethers.

(b)

The formation of five-membered ring ethers is an important goal in synthetic organic chemistry because tetrahydrofurans are contained within a number of antitumor natural products. Toward that end, a one-pot synthesis of a bis-THF containing compound was developed (Eur. J. Org. Chem. 2010, 6263–6268). Suggest a mechanism for this transformation.

Show how you would synthesize each compound using methylenecyclohexane as your starting material.

(a)

Show how you would accomplish the following synthetic conversions.

c. 3-methylpent-1-ene → 3-methylpentan-2-ol

Explain why acid-catalyzed hydration would be a poor choice for the reaction in (c).