# Textbook: Carey and Giuliano 8th Ed. (2010)

## Individual Problems

Problem # 721

Rank each of the four compounds below in order of decreasing acidity (1 = most acidic).

Problem # 724

Use curved arrows to show the formation of the tetrahedral intermediate of a Fischer esterification reaction (shown below). There are three steps in total.

Problem # 708

The overall mechanism for Fischer esterification is shown below. This isn't a real mechanism, just an outline.

Methanol (the nucleophile) attacks the carbonyl carbon, forming a tetrahedral intermediate, which then loses a water to reform the carbonyl. This mechanism is called nucleophilic acyl substitution.

Use curved arrows to draw a full mechanism for this reaction. I've included structures for you to use as a guide.

This reaction takes place under acidic conditions, so the mechanism you draw will be similar to those in problem 706.

Problem # 717

Rank each of the eight compounds A through H below in order of decreasing acidity (1 = most acidic).

Don't get intimidated! What are the differences between these compounds?

Consider electron withdrawing groups (EWG), resonance, hybridization, and the functional group of the acidic proton.

Problem # 720

Base your answers to the three problems below on your knowledge of electron donating groups and electron withdrawing groups (EDG and EWG).

a) Based on the pKa's listed below, Is formic acid more or less acidic than acetic acid? Propose an explanation why.

b) If acetic acid were added to a pH = 4.7 buffer solution, what percentage of it would be in its acetate (conjugate base) form?

c) Methoxy (-OCH3) is usually considered an EDG. But based on the pKa of methoxy acetic acid, do you think this is always the case? Explain.

Problem # 725

A chemist carried out a Fischer esterification using methanol that was isotopically labeled with 18O (indicated with an asterisk).

Which one of the esters below (A-D) was formed?

Problem # 723

Show how to prepare each compound from vinyl benzene.

How would you prepare the methyl ester of each compound?

## Mendel Sets

MS 919 - Nucleophilic Acyl Substitution and Addition Submitted by Matt on August 6, 2011.

Textbook and Chapters: Carey and Giuliano 8th Ed. (2010), Chapters 17, 18, 19

Keywords: carbonyl hydrates, nucleophilic acyl addition, nucleophilic acyl substitution

Description: The most important mechanism in second semester organic chemistry. Goes over carbonyl addition/substitution mechanisms under both acidic and basic conditions.

Total Problems: 6

MS 922 - Carboxylic Acids Submitted by Matt on August 7, 2011.

Textbook and Chapter: Carey and Giuliano 8th Ed. (2010), Chapter 18

Keywords: acid strength, carboxylic acids

Description: Goes over topics related to carboxylic acids:

• Factors that influence acidity
• Dicarboxylic acids, pK1 and pK2
• Buffer solutions, pH and pKa
• Synthesis problems involving carboxylic acids
• Fischer esterification

Total Problems: 7