3. Acids and Bases

Which of the following best describes the products formed in the acid-catalyzed hydration of $C_2{H}_4$ (ethylene) with water?

We discuss the following reactions in subsequent chapters. Given the mechanisms shown, draw the mechanism of the reverse reaction.

(a)

In each case, circle the stronger nucleophile.

(d)

Identify the arrows shown by type and predict the product that should result.

(e)

Identify the nucleophile and the electrophile in each of the following reactions.

(a)

In the context of the $S{N}_1$ reaction mechanism, which step is considered the rate-determining step?

The product of the Stille coupling reaction (A) tautomerizes in a basic solution to give compound B. B spontaneously converts to C.

(c) Suggest a mechanism for the conversion of B to C

Identify the arrow types that are shown in each of these arrow-pushing mechanisms.

(iv)

Given a reaction profile diagram with $y$-axis labeled as energy and $x$-axis labeled as reaction coordinate, which point(s) on the curve correspond to the transition state(s)?

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

Which of the following best describes the difference between organic and inorganic intermediates in a reaction mechanism?

Which energy diagram best represents a two-step reaction mechanism with a high-energy intermediate?

We show in Chapter 20 that α , β-unsaturated ketones are electrophilic at C₄. Rationalize this observation.

For practice in recognizing mechanisms, classify each reaction according to the type of mechanism you expect:

1. Free-radical chain reaction

2. Reaction involving strong bases and strong nucleophiles

3. Reaction involving strong acids and strong electrophiles

(c)

Show an arrow-pushing mechanism that forms the product on the right from the reactant at left. Two arrows are necessary in each reaction.

(a)