Amines - 6 Flashcards
How do you name amines
-amine
amino-
Why are amines so reactive
The lone pair of electrons on the nitrogen - due to polar N-H bond
What is the shape/bond angle are amines around the N
Trigonal pyramidal
107 degrees
What type of intermolecular forces do amines have
Hydrogen bonding due to polar N-H bond and lone pair of electrons on N atom
Do amines have stronger or weaker intermolecular forces than alcohols
Weaker, as the N has a lower electronegativity than O
So, weaker hydrogen bonding
How can amines act as bases
The lone pair on the nitrogen atom accepts a proton
How can amines act as nucleophiles
When they bond with an electron-deficient C atom
What is the product from the basic action of an amine with water
RNH3+ ammonium ion, which forms a salt with an anion
Write and equation for methylamine reacting with HCl
H2C-NH2 + HCL ——> H3C-NH3+ Cl-
In order to be the strongest base, what must a particular amine have
Greatest electron density around the N atom, making it a better electron pair donor
What effect do alkyl groups have on electron density and base strength
Increases electron density around N
Making it a stronger base
How would you maximise the yield of the primary amine
Use excess ammonia
What type of mechanism is the reaction of a haloalkane with a cyanide ion
Nucleophilic substitution
How do you get from a nitrile to a primary amine
Reduction
Nickel catalyst
What conditions are needed to form nitrobenzene from benzene
[H2SO4], [HNO3]
To form NO2+ ion
How do you form ammonium chloride salt from nitrobenzene
Reduce using HCL
Forms ammonium salt with Cl- ions
RTP
What mechanism is used for forming amides from acyl chlorides and amines
Nucleophilic addition
What two methods can be used to form aliphatic amines
Reaction of NH3 and halogenoalkanes
Reduction of a nitrile compound
why do amines behave as Bronsted-Lowry bases
The lone pair of electrons on the nitrogen atom can accept a proton
Forming a dative covalent bond
Describe the reactions of amines with acids
Amines neutralise acids to form salts
