Chapter 20 Flashcards
(38 cards)
The combination of a carbonyl group and a hydroxyl group on the same carbon atom is called a _______
carboxyl group
Terminology:
1) -COOH:
2) R-COOH:
3) R-COO(-)
1) carboxyl
2) carboxylic acid
3) carboxylate ion
Classification of carboxylic acids:
1) _______ acids: have an alkyl group bonded to the carboxyl group
2) _______ acids: have an aryl group
3) _______ acids: long chain of aliphatic acids
1) aliphatic
2) aromatic
3) fatty
- more than 14 C
Common naming of carboxylic acids:
The position of substituents is labeled with Greek letters starting with the C atom next to the carboxyl carbon. What is the order?
1) α
2) β
3) γ
4) δ
5) ε
- Carboxylic carbon doesnt count towards greek letters
IUPAC:
1) remove the -e from the alkane name and replace it with the ending _______
2) the carbon of the carboxyl group is number _____
3) the carboxyl group takes priority over all functional groups
1) oic acid
2) 1
3) highest priority
IUPAC:
Unsaturated acids are named using the name of the corresponding alk___e, or alk___e with the final -e replaced by -oic acid
en
yn
IUPAC:
If carboxylic acid on benzene then it is called _______
benzoic acid
IUPAC:
if 1 carboxylic acid attached to a ring, then name it like a cycloalkane followed by ending _______
carboxylic acid
IUPAC:
Dicarboxylic acids named simply by adding the suffix _______
- if cyclic then treat it as a _______
Dioic acid
ex) 2-phenyl-pentanedioic acid
substituent
ex) 1,3-cyclopentane dicarboxylic acid
If there’s a cyclic dicarboxylic acid, then the suffix _______ is used
dicarboxylic acid
- add after root
ex) 1,3-cyclopentane dicarboxylic acid
Structure of carboxyl group:
- the sp2 hybrid carbonyl C atom is _______, with nearly trigonal bond angles
- the OH bond also lies in this plane, _______ with the C=O bond
planar
eclipse
Carboxylic acids boil at considerably _______ temps than alcohols, ketones, or aldehydes of similar weight because the carboxylic acids form a stable hydrogen bond _______
higher
dimer
Aliphatic acids with more than _____ carbons are solids at room temperature
8
Double bonds (especially cis) _______ the melting point
lower
ex) on 20-3 in notes
Solubility:
- Water solubility of carboxylic acids _______ with the increasing length of the carbon chain (@ how many carbons is it immiscible)
- very soluble in _______
- Soluble in _______ solvents like chloroform: H-bonds of the dimer are not disrupted by the nonpolar solvent
decrease
- 5 or more carbons
alcohol
non-polar
What are the 2 main factors that determine acidity of carboxylic acids?
1) resonance
- quality over quantity
2) substituent effects
- quantity or distance
- EWG :)
- EDG :’(
If a molecule has 2 carboxylic acids, the first deprotonation turns one of them into an _______, which does what to acidity
EDG
lowers
- 2 - charges are also very unstable
In aromatic rings, acidity effects are strongest for substituents in the _______ and the _______ positions (mainly)
ortho
para
- for EWG
CA reacts with bases such as NaOH and NaHCO3 to form _______
carboxylate salt
The basic hydrolysis of fats and oils produces soap, this reaction is known as (_______) forms fatty acid salt which is “soap”
saponification
A bunch of soap molecules is called a _______ which has the polar carboxylate ion (outside) and nonpolar hydrocarbon (inside)
micelle
What kind of oxidation should you do to form Carboxylic acid from 1° alcohols and aldehydes? (3)
1) excess NaOCl, TEMPO
2) Cr reagent with acid
- Na2Cr2O7, H2SO4
3) Ag2O
- only aldehydes
What reagents should you use to form CA from alkenes?
1) KMnO4 , acid
- any H on the double bond turns into OH in addition to adding a carbonyl to C
What reagents should you use to turn an alkyne into carboxylic acid?
KMnO4
or
1) O3 2)H2O
