Revision
It’s the condition to oxidise primary alcohols to form carboxylic acid.
What is “heat under reflux”?
It’s the sign in the question mark that shows the reactivity: RCOCl ? R-Cl ? Ar-Cl
What’s the greater-than sign?
The pH value of weak acid.
What is pKa value for acids?
It’s the increment of oxidation number.
What is oxidation?
An example for this reaction is hydrolysis of acyl chloride.
What’s an example for addition-elimination reaction?
It’s the reagent that forms carboxylic acid after heating with sulfuric acid.
What are nitriles?
Very vigorously at room temperature.(NaOH)
How was the reaction of acyl chlorides with NaOH?
Electrons tends to move towards the more electronegative atoms.
What is electron-withdrawing?
Acidified potassium manganate.
What is an example of oxidising agent?
Because water as active lone pairs of electrons on an oxygen atom.
Why is water a nucleophile?
Carboxylic acid will turn into a salt and there will be hydrogen generated.
What will happen if reacting sodium with carboxylic acid?
It’s an organic compound containing a chlorine atom that don’t react with water or sodium hydroxide whatsoever.
What is chloroarene?
Because the negative charge on the anion can be delocalised over two electronegative oxygen atoms.
Why carboxylic acids are more acidic than alcohols?
It’s the gas product of oxidation of methanoic acid.
What is CO2?
Because there is elimination after addition.
Why the reaction is called “addition-elimination”?
CO2 will be liberated and salt will be formed from carboxylic acids.
What are carbonatess?
Because one lone pair on the chlorine aton can overlap with the pi-bond n the benzene ring, making the C-Cl bond stronger.
Why are chloroarenes less reactive than chloroalkanes?
Fluorine in fluoroethanoic acid is more electronegative than chlorine.
Why fluoroethanoic acid has lower pKa value than chloroethanoic acid?
It means that the test using Tollen’s agent is positive.
What does silver mirror means?
It’s used to attack acyl chlorides in addition.
What’s the role of a nucleophile in addition-elimination reaction?
It’s the catalyst to reduce carboxylic acids to alcohols.
What is LiAlH4/NaBH4?
It allows nucleophile to bond with the carbon atom before chloride ion has left, hence speeding up the reaction.
How does the double bond between carbon and oxygen have effect on the reactivity on acyl chlorides?
It will help to spread out more negative charge of the anion, making the acid become more dissociated.
What’s the effect of electronegative atoms in R groups in carboxylic acids?
It means the oxidation of ethanedioic acid using potassium manganate.
What does colour change from purple to pink indicate?
The carbon atom in -COCl group in an acyl chloride has two electronegative atoms attatched to it. Thus it will be positively charged.
Why are acyl chlorides attacked by nucleophiles?