Carboxylic Acids and Derivitives

Question 1

Inductive Effect

Answer 1

Creation of a strong dipole in a structure with different electronegative parts

Question 2

How would the acidity of the structure differ and why?

Answer 2

The 2-bromoacetic acid would be more acidic due to the inductive effect of the bromine when compared to acetic acid.

Question 3

Which will be a stronger acid?

Answer 3

Propanoic acid will be stronger because the methyl group on the 2-methylpropanoic acid donates electrons so in its base form it contributes to a more negative charge making it a less stable conjugate base

Question 4

Place the following in order of increasint BP

hexane

hexanoic acid

heptanoic acid

hexanal

hexanol

Answer 4

hexane

hexanal

hexanol

hexanoic acid

heptanoic acid

Question 5

Sapnification

Answer 5

xx

Question 6

What would happen if you treated carboxylic acid with LiAlH4 and hydronium?

Answer 6

It would be reduced to a primary alcohol

Question 7

How would you reduce a carboxylic acid to an aldehyde?

Answer 7

Treat it with DIBAL-H at low temps

Question 8

Decarboxylation

Answer 8

CO2 is a product

Question 9

Nucelophilic substitution reactions with carboxylic acids

Answer 9

The hydroxyl group can serve as a very good leaving group if turned to water so nucelophilic substitutions are really good for carboxy-acids. The OH essentially gets replaced with whatever.

eg

FIscher esterification

Question 10

Hell Volhard Zelinsky Halogenation

Question 11

What rxn:

Answer 11

DIBAL

Question 12

True or false: The product of a Hell-Volhard-Zelinsky reaction followed by hydrolysis is bound to be more acidic than the starting substrate

Answer 12

This statement is true. The Hell-Volhard-Zelinsky reaction followed by hydrolysis results in an α-brominated carboxylic acid. The inductive effect of the bromine on the α-carbon is guaranteed to make the resulting carboxylic acid more acidic than the parent chain that was reacted with a halogen and a catalytic amount of trihalogenated phosphorus.

Question 13

What are the carboxylic acid dervitives?

Answer 13

Esters, Amides, and Acid Anhydrides

Question 14

How would you name the following:

Answer 14

N-Methyl-Propanamide

Question 15

What do you call a cyclic amide?

Answer 15

Lactams

Question 16

True or False: amides tend to have weaker intermolecular interactions than alcohols and carboxylic acids (and therefore lower BPs)

Answer 16

True

Question 17

Name:

Answer 17

Ethyl hexanoate

Question 18

How would you name a ringed ester?

Answer 18

Lactone

Question 19

True or False: Esters cannot hydrogen bond

Answer 19

True, this makes them rather volatile

Question 20

True or False: Amids and esters dont tend to engage in acid base chemistry

Answer 20

true

Question 21

If you condensed two acetic acid molecules, what would you get?

Answer 21

Acid anhydride

Question 22

Name:

Answer 22

Butanoic ethanoic anhydride

Acid anhydrides are named for their alkyl chains in alphabetical order

Question 23

Place the following in order of least to most reactive:

acid anhydride

caroxylate

carbocylic acid

acyl chloride

ester

acid anhydride

Answer 23

caroxylate

carbocylic acid

ester

acid anhydride

acyl chloride

Question 24

What is the product?

Answer 24

This is the Hell-Vollhard-Zelinsky halogenation reaction product prior to hydrolysis: an α-brominated acyl halide.