13. Alcohols and Carbonyl Compounds

Which two carbonyl compounds are required for the synthesis of morachalcone A via nucleophilic addition?

Why is a ketone more reactive/electrophilic than an ester?

Which of the following best describes the movement of electrons (curved arrows) during the nucleophilic addition that converts an ${\mathrm{enolate}}_{\mathrm{ion}}$ to its $\mathrm{keto}$ form?

Which product is most likely formed when a ketone reacts with a nucleophilic hydride ion source such as ${\mathrm{Na}}_{\mathrm{BH}}{4}_4$ or ${\mathrm{Li}}_{\mathrm{AlH}}{4}_4$?

Which product is typically formed when a $\mathrm{ketone}$ reacts with a $\mathrm{primary}\mathrm{amine}$ in a nucleophilic addition reaction followed by elimination?

Which of the following best describes the major organic product formed when a $\mathrm{Grignard}$ reagent reacts with an $\mathrm{aldehyde}$ followed by aqueous workup?

When a simple unsymmetrical ketone such as $C_3{H}_{6}O$ (propanone) is treated with base, which of the following best describes the enolates that can be formed?

Which of the following best describes the nucleophilic addition of an enolate ion to a carbonyl group in an aldol reaction?

Propose a mechanism for the following reactions:

a.

Within each set of structures, indicate which will react fastest, and which slowest, toward nucleophilic addition in basic conditions.

(c)

Based on the analysis you used in Assessment 17.3, which carbonyl would you expect to react most quickly with a nucleophile?

(a)

a. Could a nucleophile ever add to C₃?

b. Why or why not?

What product is formed when 3-methyl-2-cyclohexenone reacts with each of the following reagents?

c. HBr

d. CH₃CH₂SH

Within each set of structures, indicate which will react fastest, and which slowest, toward nucleophilic addition in basic conditions.

(a)

Nucleophilic addition to the α,β-unsaturated ketone shown can occur at either C₂ or C₄. Why?