17.5.1 - Amines and their preparations Flashcards
What is the structural formula of methyl amine?
CH3NH2
What are the reagents and conditions for forming amines from halogenoalkanes?
Reagents: Halogenoalkane, ethanol solvent, ammonia.
Conditions: Heated in a sealed container.
What is the formed when equal ratios of chlromethane and ammonia react and why is this a problem?
Methyl amine is formed.
This can react again with the original halogenoalkane to form dimethyl amine which is an unwanted product.
In the reaction between a halogenoalkane and ammonia, how can we prevent any unwanted products being formed?
Use excess ammonia.
When amines are prepared from nitriles, what are the reagents used?
Lithium tetrahydridoaluminate and dry ether to ensure no water affects the reaction.
What is the equation for the reduction of ethanenitrile into an amine?
CH3CN + 4(H) = CH3CH2NH2
What is the type of the reaction when ammonia reacts with a halogenoalkane to form an amine?
Nucleophilic substitution.
What is the name of the reaction when a nitrile is converted into an amine?
Reduction
Phenylamine can be formed from nitrobenzene.
What are the reagents and conditions for this reaction?
Reagents: Tin (reducing agent) and conc. HCl
Conditions: Heat under reflux.
What is a property of phenylamine that is significant when it is formed from nitrobenzene?
It is basic and will react with the acid to form a phenylammonium ion.
How can a phenylammonium ion converted back into phenylamine?
Adding sodium hydroxide solution.
