13. Alcohols and Carbonyl Compounds

Which of the following alkyl halides could be successfully used to form a Grignard reagent?

How could the following compounds be prepared, using cyclohexene as a starting material?

d.

A laboratory student added 1-bromobutane to a flask containing dry ether and magnesium turnings. An exothermic reaction resulted, and the ether boiled vigorously for several minutes. Then she added acetone to the reaction mixture and the ether boiled even more vigorously. She added dilute acid to the mixture and separated the layers. She evaporated the ether layer, and distilled a liquid that boiled at 143 °C. GC–MS analysis of the distillate showed one major product with a few minor impurities. The mass spectrum of the major product is shown here.

(a) Draw out the reactions that took place and show the product that was formed.

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Starting with cyclohexane, how could the following compounds be prepared?

e.

A chemist attempted the reaction below, one we introduce in Chapter 17, expecting the reaction between a strong nucleophile and a ketone in water to give an alkoxide product.

(a) Why did the reaction fail?

(b) How could the reaction conditions be changed to give a successful reaction?

Give the expected products of the following reactions. Include a protonation step where necessary.

(a) 2,2-dimethyloxirane + isopropylmagnesium bromide

(b) propylene oxide + n-butyllithium

(c) cyclopentyloxirane + ethyllithium

Fill in the boxes:

Predict the product of the diorganocuprate cross-coupling reactions shown.

(a)

Predict the product of the diorganocuprate cross-coupling reactions shown.

(b)

Based on the stereochemical result alone, how can you tell that this reaction does not proceed by an Sₙ2 mechanism?

Predict the product of the following epoxide opening reactions.

(a)

Predict the product of the following epoxide opening reactions.

(b)

A chemist failed to generate the alcohol using the reaction shown here.

(a) Suggest a reason why this reaction did not work as written.

In lieu of quenching the product of Grignard addition to a carbonyl with acid, alkyl halides can be added directly to generate ether products. Predict the product and show the mechanism of this process.

Predict the products formed when cyclohexanone reacts with the following reagents.

(f) PhMgBr and then mild H₃O⁺