Organic - 3.9 Carboxylic Acids & Derivatives Flashcards
What do carboxylic aids form when reacted with carbonates?
Carbon dioxide
Why are Carboxylic acids soluble in water?
Short chains are very soluble in water.
Highly polar carbonyl groups and hydroxyl groups can form hydrogen bonds with water
What salts do Carboxylic acids form?
Carboxylate
What is the test for Carboxylic aids?
- Add a spatula of sodium carbonate or sodium hydrogen carbonate to the solution.
- If it is a Carboxylic acid, effervescence is observed
- The gas can be collected and bubbled into lime water which should turn cloudy (CO2 present)
What two reactants form an ester?
Carboxylic acid and an alcohol
Where does the ester name come from?
The beginning comes from the alcohol and the end comes from the carboxylic aid.
e.g.
Methanol and propanoic acid forms methyl propanoate.
What is esterification?
The process of combining a carboxylic acid with alcohol to form an ester and water.
What is the catalyst in esterification?
Sulfuric acid
Give 5 uses of esters
Plasticisers
Solvents
Perfume
Food flavour
Biodiesel
Give two natural esters
Fats and oils
Soaps
What is ester hydrolysis?
The breaking of an ester using water resulting in a carboxylic acid and alcohol
What is saponification?
The process of cleaving esters into carboxylate salts and alcohol using sodium hydroxide.
What is the IUPAC name for glycerol?
propane-1,2,3-triol
What is the equation for the formation of biodiesel?
Vegetable oil + methanol -> glycerol + methyl ester
Biodiesel is a mixture of methyl esters
What are acid derivatives?
Compounds that are related to carboxylic acids as the OH group has been replaced with something else.
What is an acyl chloride?
What is the suffix of acyl chlorides?
Carboxylic acid with Cl replacing OH
-anoyl chloride
What is an acid anhydride?
What is the suffix?
Formed when two molecules of a carboxylic acid join together water is eliminated.
-anoic anhydride
What is an amide?
What is the suffix?
A carboxylic acid with NH2 replacing OH
-anamide
What is acylation?
The process of replacing a hydrogen atom in certain molecules with an acyl group.
What is the acylation reaction called?
NucleophilIc addition-elimination
What are the three products of acylation?
Amides
Carboxylic acids
Esters
What two compounds undergo acylation?
Acyl chlorides
Acid anhydrides
What are the four nucleophiles in a nucleophilic addition elimination reaction?
Water
Alcohol
Ammonia
Amine
What are the advantages of using ethanoic anhydride over ethanoyl chloride when manufacturing aspirin?
It is cheaper
It is safer to use as it is less corrosive, reacts slowly with water and doesn’t produce dangerous hydrogen chloride fumes.
Product of acyl chloride and water
Carboxylic acid and HCl
Product of acyl chloride and alcohol
Ester and HCl
Product of acyl chloride and ammonia
Amide and HCl
Product of acyl chloride and primary amines
N-substituted amide and HCl
Product of acid anhydride and water
Two carboxylic acids
Product of acid anhydride and alcohol
Ester and carboxylic acid
Product of acid anhydride and alcohol
Ester and carboxylic acid
Product of acid anhydride and ammonia
Amide and carboxylic acid
Product of acid anhydride and primary amines
N-substituted amide and carboxylic acid
Mechanism for nucleophilic addition-elimination
Step 1
1) Arrow from electron pair on nucleophile to carbon on C=O.
2) Arrow from double bond on C=O to oxygen on C=O
Step 2
1) Arrow from electron pair on top O
2) Arrow from C-Cl bond to Cl
3) Arrow from O+-H/N+-H bond at bottom to N+/O+
Step 3
1) Forms C=O and C-OH/OCH2CH3/NH2/NHCH3
