6.1 Arenes Flashcards
Why is phenol more reactive than benzene?
The p orbital electrons in the O are donated into the delocalised pi system of electrons in the aromatic ring, making it more nucleophilic and electron dense
Rate benzene, phenol and alkene in terms of reactivity from most to least
1) Alkene
2) Phenol
3) Benzene
Why is phenol a stronger acid then aliphatic alcohols?
Because the ring helps weaken the O-H bond, so the H is more easily lost
Phenol reacts _______ with Na to form ______ ______ + Hydrogen
Vigorously to form sodium phenoxide
How can you distinguish between phenol and a carboxylic acid?
Phenol has no reaction with carbonates but a carboxylic acid does
What is a carbonyl functional group?
C=O
2,4 DNPH reacts with __________ to form an orange precipitate.
Aldehydes and ketones
What can Tollens reagent test for?
Aldehydes, forms a silver precipitate
How can Brady’s reagent be used to identify ketones and aldehydes?
The recrystallised precipitate has a specific melting point which can be compared to known data values
What does NaBH4 do?
Reduce carbonyls to alcohols
What ion is produced to reduce carbonyls?
H- hydride ion
What happens to a carboxylic acid in water?
It dissolves
What is the general structure of an acid anhydride?
ROCOCOR
What is the products of acid anhydride + alcohol?
Ester and carboxylic acid
How do you esterify phenol?
React with acyl chloride ONLY
