3. Acids and Bases

Which statement best describes the purpose of adding curved arrows to the reactants in an organic reaction mechanism?

In each reaction, label the reactants as Lewis acids (electrophiles) or Lewis bases (nucleophiles). Use curved arrows to show the movement of electron pairs in the reactions. Draw any nonbonding electrons to show how they participate in the reactions.

(b)

Would you expect the following species to be electrophiles or nucleophiles? Some may be both. Explain your answer.

(c)

Propose a mechanism for the rearrangement that converts an ⍺-hydroxyimine to an ⍺-aminoketone in the presence of a trace amount of acid.

In organic reaction mechanisms, curved arrows are used to illustrate the flow of electrons. Given the reaction conditions of a nucleophile attacking an electrophile, what does a curved arrow represent in the mechanism?

Which statement best describes the purpose of drawing curved arrows in an organic reaction mechanism?

Which of the following steps could be found in an $S{\mathrm{N}}_1$ reaction mechanism?

In a radical halogenation reaction, which mechanistic step involves the homolytic cleavage of a halogen molecule to generate two halogen radicals?$X{2}_{}\to 2X•$

Which is the correct depiction of the transition state for the $S_{\mathrm{N}}2$ reaction shown below?

Which statement best describes the purpose of adding curved arrows in illustrating an organic reaction mechanism?

In the following reaction, what is the missing reagent (a)? ${\mathrm{CH}}_3\mathrm{CH}=\mathrm{CH}2$ → ${\mathrm{CH}}_3{\mathrm{CH}}_2{\mathrm{CH}}_2\mathrm{Br}$

Which of the following best describes the detailed mechanism for a typical polar reaction such as the nucleophilic substitution of $R_{\mathrm{Br}}$ with $\mathrm{OH}-$ to form $R_{\mathrm{OH}}$ and $\mathrm{Br}-$?

Which of the following statements correctly describes the products, including all possible stereoisomers, formed when 2-butene reacts with bromine (${\mathrm{Br}}_2$) in an inert solvent?

Label the reactants in these acid–base reactions as Lewis acids (electrophiles) or Lewis bases (nucleophiles). Use curved arrows to show the movement of electron pairs in the reactions.

i.

Provide a reasonable arrow-pushing mechanism for the following Lewis acid–Lewis base reactions.

(a)