13. Alcohols and Carbonyl Compounds

What starting material is required in order to synthesize each of the following compounds by ring-closing metathesis?

a.

Muscalure is the sex attractant of the common housefly. Flies are lured to traps filled with bait that contain muscalure and an insecticide. Eating the bait is fatal. How could you synthesize muscalure using 1-bromopentane as one of the starting materials?

Using the epoxide shown, addition of an organolithium reagent, when followed by an acid quench, produces only the starting epoxy alcohol. Why? How could the reaction be modified to produce the desired molecule? [Hint: Look back at Section 13.14.]

Predict the product of the following epoxide addition reactions.

(a)

A variety of organometallics, which as strong nucleophiles can react with epoxides, are introduced in Chapter 16. Predict the product of these reactions. [Hint: Assume the carbon–metal bond in each is ionic, with the carbon possessing the negative charge.]

(c)

Give the structures of intermediates A through H in the following synthesis of trans-1-cyclohexyl-2-methoxycyclohexane.

Predict the major products of the following reactions, and give the structures of any intermediates. Include stereochemistry where appropriate.

(o)

For each of the following carbonyl addition reactions, would you expect a racemic mixture or a mixture enriched in one stereoisomer? In each case, draw both possible stereoisomeric products.

(a)

Predict the product of the following aldehyde and ketone addition reactions.

(a)

Predict the product of the following aldehyde and ketone addition reactions.

(c)

What other product is formed in this reaction?

Using the given starting material, any necessary inorganic reagents and catalysts, and any carbon-containing compounds with no more than three carbons, indicate how each of the following compounds can be prepared:

f.

What organometallic compound is formed from the reaction of excess methylmagnesium chloride and GaCl₃?

What bromo-substituted compound would be required to react with (CH₂=CH)₂CuLi in order to form each of the following compounds?

b.

What alkyl halide reacts with lithium divinylcuprate [(CH₂=CH)₂CuLi] for the synthesis of each of the following compounds?

a.

b.