amines Flashcards
primary amine
general formula RNH2
name - …..amine
secondary amine
general formula RR’NH
name - N-……-N-…..
tertiary amines
general formula RR’R’‘N
name put N- infront
quaternary amines
have a positive charge
example tetramethyl ammonium salt
amine as bases
lone pair on nitrogen can accept a proton to form an ammonium ion
strength of amines as bases
strength of base is determined by how available the nitrogen lone pair is to accept a proton
the positive inductor effect is the availability of an alkyl group to release electron density through a covalent bond
phenyls are weaker as lone pair on nitrogen delocalises into the phenyl ring
use of quaternary ammonium salts
used in hair conditioner and fabric softener
called cationic surfactants
nucleophilic addition
you cant control the amount of primary, secondary and tertiary amines that form so the products will be a mixture
not an efficient way of forming an amine
to ensure a higher yield of the primary amine
use a large excess of ammonia
further substitution requires .,.
excess haloalkane
haloalkane alkyl group is added to the N
reduction of nitriles
if a primary amine is the desired product a reduction of a nitrile can be used
haloalkanes undergo a nucleophilic substitution with a cyanide ion in ethanolic and aqueous conditions
nitrile formed can be reduced to an amine functional group
requires hydrogen and nickel catalyst
more expensive
formation of phenylamine
nitrobenzene is made by electrophilic substitution
nitro group reduced to amine functional group which needs hcl and tin catalyst
as this process takes place in presence of hcl the product formed can react with hcl to form phenylammonium chloride
to prevent this naoh can be added which is a strong base
uses of amine
amines can be used to form amides
amides used to make
polymers like nylon
dyes
drugs and pharmaceuticals