Chapter 9: Carboxylic Acid Derivatives

Question 1

carboxylic acid derivatives

Answer 1

amides, esters, anhydrides

Question 2

amides replace the OH on the carboxyl group with _____

Answer 2

NR2

Question 3

esters replace the OH on the carboxyl group with _____

Answer 3

OR

Question 4

anhydrides replace the OH on the carboxyl group with _____

Answer 4

OCOR

Question 5

carboxylic acid derivatives are formed by which reaction mechanism?

Answer 5

condensation reaction: a reaction that combines 2 molecules into 1, while losing a small molecule (water in this case)

(the water is formed from the OH on the carboxylic acid and the H on the nucleophile)

Question 6

amide general structure

Answer 6

Question 7

amides nomenclature

Answer 7

replace “-oic acid” (for carboxylic acid) suffix with “amide”

alkyl substituents on the nitrogen are listed as prefixes with the letter N

Question 8

lactams

Answer 8

cyclic amides

Question 9

ester structure

Answer 9

Question 10

esters nomenclature

Answer 10

the esterifying group (substituent bonded to the oxygen) is a prefix; the suffix “-oic acid” is replaced with “oate”

Question 11

Fischer esterification

Answer 11

carboxylic acids and alcohols condense into esters under acidic conditions

Question 12

lactones

Answer 12

cyclic esters

Question 13

boiling points: ester vs carboxylic acid

Answer 13

esters usually have lower boiling points than their related carboxylic acid because they lack hydrogen bonding

Question 14

triacylglycerols

Answer 14

esters of long-chain carboxylic acids (fatty acids) and glycerol

Question 15

saponification

Answer 15

the process by which fats are hydrolyzed under basic conditions to produce soap

image shows saponification of a triacylglycerol

Question 16

hydrolyzed meaning (hydrolysis)

Answer 16

the cleavage of chemical bonds by the addition of water

OH goes on one molecule, H goes on the other

Question 17

anhydrides general structure

Answer 17

Question 18

the following structures are examples of:

Answer 18

cyclic anhydrides

Question 19

anhydride synthesis

Answer 19

they are synthesized by a condensation reaction between 2 carboxylic acids

Question 20

boiling point: anhydride vs carboxylic acids

Answer 20

anhydrides often have higher boiling points than carboxylic acids due to their much greater weight

Question 21

relative reactivity of carboxylic acid derivatives toward nucleophilic attack

Answer 21

most reactive → least reactive

anhydrides → esters → amides

Question 22

steric hindrance

Answer 22

when a reaction does not proceed because the substituents crowd the reactive site

Question 23

steric hindrance and carboxylic acid derivatives

Answer 23

the size of the leaving group can affect the derivative’s ability of a nucleophile to access the carbonyl carbon, which affects the reactivity of the derivative to nucleophilic acyl substitution

Question 24

induction

Answer 24

the uneven distribution of charge across sigma bonds because of differences in electronegativity

Question 25

conjugation

Answer 25

the presence of alternating single and multiple bonds

Question 26

strain in cyclic derivatives

Answer 26

lactams and lactones are more reactive to hydrolysis because they have more strain

Question 27

protecting groups

Answer 27

substituents which can be used to increase steric hindrance to decrease the reactivity of a particular portion of a molecule