Chapter 27 To 27.2 Flashcards
What are amines
Amines are organic compounds that are derived from ammonia NH3, but here one or more hydrogens are replaced with a carbon ring or a Carbon chain
What’s the difference between aliphatic and aromatic amines
We just said amines are where hydrogens replaced with carbon ring or chain
Where it is attached to an aromatic ring r group it’s an aromatic amine
If just straight branched chain = aliphatic amine
How are amines classified (like everything else in chemistry)
Based on how many r groups of carbon chain/ Arya group is attached to the N makes it primary secondary or tertiary
How to name amines if they are primary
2 rules
And if they secondary tertiary same r group?
1) if it’s on carbon one, it just becomes chain amine = so like ethyl amine
2) if it’s not on carbon one but still primary, then say amino - position - chain
So like amino-2-propane means amine group is in the middle of the carbons
2) Just say di (r group) amine if it’s the same
If tertiary or secondary amines, how to name if DIFFERENT R GROUPS
(Rules)
Here you will need to do an N subsidised Of thr LARGER GROUP
- BASICALLY the largest group gets the suffix amine .
- any other group gets N- group to it, and if it’d tertiary then it will be N-group-N-group groupamine
- finally order which group comes first based on ALPHABET
That’s why it’s N-ethyl - N - methylpropylamine
Because propyl biggest so got amine, ethyl alphabetic so first!
How does amines act like a base and why?
What happens when they accept the proton
- what’s the charge!
Because we know a BL base is one that accepts protons, and here the amine having a nitrogen has a lone pair, and thus can accept a proton
When they accept the proton, the H+ forms a dative covalent bond .
- by conservation of charge itd now positive , accepting a proton increases positive charge by one
How do amines react with acids to produce
Why
What is produced
They produce a SINGLE SALT AND THATS IT
Why?
- because they act as bases so accept a proton, but then they can attach the the remaining negative ion , so the whole acid basically adds on
= one full addition reaction
What is similar to tje reaction between an amine and an acid
The reaction between ammonia and an acid
This is just an addition reaction, and amines being DERRIVATIVE will follow
With sn acid the hydrogen is only replaced by either a metal OR AMMONIUM ION, therefore this simple addition reaction happens
How to prepare primary amines what are the steps
This is done beginning with AMMONIA
As N has a lone pair , it can act as a nucleophile (donate a pair of electrons) to a haloalkane in a NUCLEOPHILIC ADDITION REACTION
1) so first the ammonia pure reacts with primary haloalkane. This forms a FULL SALT AGAIN In propylammonium chlroide
Now as it kinda got a hydrogen, it can react with alkali and give hydrogen to make water and chlroide ion react with something else
2) ammonium salt reacts with NaOH and forms NaCl and H2O alone with primary amine
This forms primary amine
What are the conditions for making exactly a primary amine and why (2)
1) is that Ethanol is used as the solvent so that halolakne doesn’t substitute with water to make alcohols instead
2) EXCESS ammonia used to LIMIT THR SMOUNT OF FURTHER SUBSTITION OF AMINE GROUP atoms form secondary and tertiary amines
Why is method to make primary amine not the bets for pure
Thus how can we make secondary and tertiary
Thr primary amine made can easily react with another halolakne as it still got lone pair to start process again
This is what happens 1) new primary amine reacts with halolakne addition to form ammonium chloride salt
2) reacts with more alkali to form di prohlamine whatever , Nacl and h2o
Can do it again ti make tertiary
For,action of primary secondary tertiary summarised
React with ammoni a haloalken in a NUCLEOPHILIC addition reaction to form an ammonium salt
2) this reacts with alkali ti form nacl h20 and amine
- for primary = ethanol to ensure water doesn’t substitute with the halolakne to form alcohol instead
- excess ammonia to prevent further substation of amine group to secondary tertiary
To make tertiary secondary react primary agsin with halolakne and do again
How to make aromatic amine
Say ohenylamine
JUST REMEMBER TWO STEPS AND PRODUCTS + Condtions
By reduction of nitrobenzene
1) happens by first heating nitrobenzene under reflex with tin and concentrated hydrochloride acid to form ammonium chloride salt
2) then reacted with excess NaOH to give the phenylamine and 2 water
Overall = nitrobenzene + 1) Sn/Conc HCl and 2) excess NaOH = phenylamine and 2h2o
Heated under reflux
What is an amino acid
Amino acid is anything with an amine group, a carboxylic acid, and a variable R group
The vernal formula for it is RCH(NH2)COOH
What are alpha and beta gamma amino acids briefly
Alpha amino acids is where the amine group attached to the second carbin of the chain , and these are the standard ones we have too
Beta is third and game 4th , don’t need to know
What type of reactions can amino acids undertake in and why
Because they have both an amine group and carboxylic acid group, they can react with similar reactions to both carboxylic acids and amines
For example cabrixykic acid will react with alkali to form salt and water
Amino acids with an alkali gives?
Amino acid with acid
Amino acids with alkali gives you a salt and water, just like how normal cabroxykic acids react with alkali
) acid gives protonated amine group and negative ion
How are esters made again
Reflux acid and alcohol with catalyst and you get
So can esterificsrion happen with amino acid? How
EXACTLY HOW (reactants ), and EXACT PRODUCTS
Yes, heat amino acid with alcohol in the presence of SULFURIC ACID
- this gives you ester and water
BUT ALSO the acidic condition actually protonste the amino group, so it becomes H3N+!
Reaction summary amino acid
With alkali o form salt and water
With alcohol heated and sulfruci acid to give ester protonsted and water
How do we know already how amides are made and now with amino how else made
Originally made with ammonia reacting with acyl chlroide and amides
But amino acid = amine group reacts with carbixykic acid of another to form CONH bond
How to classify amides
Again how many r groups attached to the nitrogen = primary secondary tertowtu
What is a stereoisomer
What is an OPTICAL ISOMER
Compounds that have the same structural formula but differnt arrangement if atoms in space
Optical isomers are where the same molecule can form two non superimposable MIRROR images of each other
What can make something an optical isomers
If it has a chiral centre
- a chiral centre is where a carbon is attached to 4 DIFFERENT GROULS (can be two as a ring)
- if it has a chiral centre, it can thus produce two non superimposable mirror images of each other’s which are optical isomers or enantiomers
How many optical isomers or enantiomers for every chiral centre
Always 2 enantiomers per chiral carbon
Some things about drawing chiral carbons and identifying?
Can’t be double bond or two methyl groups eliminate
Look for hidden hydrogen
And drawing must be 3 d tetrahedral
Amine amide amino acid reaction summary
Amine base = acid to form ammonium salt (whole thing )
2) forming amines through halakoane , ammonia, then Nacl
3)FORMING ARMOATIC AMINE = 1) react with tin and hcl reflux 6H 2) react with NaOH to form ammonium chloride salt and 2 water
4) amino acid amine group basic will react with acid and PROTONATE thr nH3
- amino acid carboxylic react with base salt and water and alcohol with h2so4 to make ester protonated
5) amides can be made by reactions amino acid with each other
What is condensation polymerisation about
Where two functional groups join and lose a small molecule typically water / hcl and makes a long polymer
Such as polyester, need di csbdocylic scid and di oil , or just both on each
Or polyamide , like protein is a polyamide, need both
Each time a small thing ismlost
Okay so two types of condensation polymerisation, how can you do with one or two monomers?
One monomer means it has both functional groups
Two monomers mean each monomer has the same functional group but twice
Condensation polymerisation for esters? How can you do both ways
What’s third way? What’s made here
1) diol and di carbox
2) both
You can also use a diacyl chrlodie instead of carboxylic acid , it’s just that HCLS ARE FORMED INSTEAD
Again what can you use instead of carboxylic acid to make polyesters, and what’s formed
Acyl chlroides + alchol still makes esters, so can use this, just HCLS are made instead
How to show starting from n units to n units of water if polymerisation and n units of polymer
This is for when there are TWO MONOMERS
So n on first monomer and second
N on polymer, open brackets
And 2n-1 watee / hcl
Again for two monomer reactions, how much water/ hcl produced
2n-1
Polypeptide?
Is just polyamide for proteins
How does hydrolysis of these polymers work again! What are the two ways?
Base hydrolysis
Acid hydrolysis
What happened in base hydrolysis again
Base hydrolysis involved using hot aqueous Na OH
What happens is the cabroylic returned is now in the form of an ion/ salt with Na
And the alchol is the same
Both cases alchol same
ALSO NON REVERSIBLE
Acid hydrolysis
Uses hot aqueous acid like hydrochrloc (so out h20 next to it)
Alchol returned as normal,
Here cabroylic also retuned as normal
BUT REVEESIBLE
Acid base hydrolysis summary
AQUEOS alkali or acid used (so NaOH/H20 or a hcl/h20)
Each cases the second thing is retuned
Alkli hydrolysis the carbox is returned as a salt or ion
Acid the cabrixykic retuned
Alklai non reversible
Acid reversible
