carboxylic acids

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

Problem # 735
 

Show how each ketone below can be prepared from sodium cyanide and either ethylene or propene.

You may also use methyl Grignard and ethylene oxide.

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 # 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 # 723
 

Show how to prepare each compound from vinyl benzene.

How would you prepare the methyl ester of each compound?

Problem # 721

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

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 # 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.