Module 6.2 Flashcards
1
Q
How many different types of amines can we get?
What are they?
A
3 types.
Primary, Secondary and Tertiary
2
Q
If we have a primary amine, how many hydrogen groups are attached to the nitrogen?
Also, how many R groups are attached to the nitrogen?
A
2 hydrogens
1 R group
3
Q
If we have a secondary amine, how many hydrogen groups are attached to the nitrogen?
Also, how many R groups are attached to the nitrogen?
A
1 hydrogen
2 R groups
4
Q
If we have a tertiary amine, how many hydrogen groups are attached to the nitrogen?
Also, how many R groups are attached to the nitrogen?
A
NO hydrogens
3 R groups
5
Q
Name the following primary amines:
CH3NH2
CH3CH2CH2NH2
A
Methylamine
Propylamine
6
Q
Name the following secondary amines:
CH3NHCH3
CH3CH2CH2NHCH3
A
N,N - Dimethylamine
N,N- Methyl propanamine
7
Q
Name the following tertiary amine:
CH3NCH3CH3
A
Trimethylamine
8
Q
Define the term base
A
A proton acceptor
9
Q
Why can amines be regarded as bases?
A
Lone pair of electrons on the nitrogen atom that is able to accept protons.
10
Q
When amines react with dilute acids, what is formed?
A
Ammonium salt
11
Q
What is meant by aliphatic?
A
Straight chained compounds
12
Q
Describe the preparation of aliphatic amines by substitution of haloalkanes
A
Aliphatic amines can be made by heating a haloalkane with an excess of ethanolic ammonia.
Reagents = Haloalkane + Excess ethanolic ammonia Conditions = Sealed in a tube. Products = Aliphatic amine + Ammonia salt
13
Q
Give a generic reaction equation for the formation of aliphatic amines by substitution of haloalkanes
A
RX + 2NH3 → RNH2 + NH4X
Haloalkane + Ammonia → Aliphatic primary amine + Ammonium halide
14
Q
In the process of preparing aliphatic amines, why is excess ethanolic ammonia used?
A
To prevent further substitution
15
Q
In the process of preparing aliphatic amines, if we use excess haloalkane, what type of product do we get?
A
A quarternary ammonium salt e.g.
16
Q
Describe the preparation of aromatic amines by reduction of nitroarenes
A
Aromatic amines are made by reducing a nitro compound such as nitrobenzene.
Nitrobenzene is reduced by heating a nitrocompound with a reducing agent ( mix of conc. HCl and tin (Sn))
After 30 minutes has passed, we add a strong base such as NaOH to the salt produced from reducing nitrobenzene to get our aromatic amine.
Reagents = Reducing agent (Mix of tin + conc. HCl) Conditions = 100 degrees celsius under reflux Products = Aromatic amine + 2H2O
17
Q
Give the generic equation for the preparation of aromatic amines
A
Nitroarene + 6[H] → Phenyl amine + 2H2O
Phenylamine is an aromatic amine
18
Q
What is the general formula of amino acids?
A
RCH(NH2)COOH
19
Q
Why can amino acids be regarded as amphoteric?
A
They have an acidic group as well as a basic group
Acidic = COOH Basic = NH2
20
Q
When an amino acid reacts with an alkali, what is produced?
A
A salt + Water
Amino acid + Alkali → Salt + Water
21
Q
When an alkali is added to an alpha amino acid, what happens to the COOH and the NH2 groups?
A
COOH becomes COO^-M+ where M is the metal from the alkali
NH2 remains the same
22
Q
What is meant by a zwitterion?
A
An ion with no overall charge because the positive and negative charges in the compound CANCEL each other out.
23
Q
What is meant by the isoelectric point
A
The pH at which there is no net electrical charge on the amino acid
24
Q
Describe the reaction of the carboxylic acid group of amino acids reacting in the formation of esters
A
The carboxylic acid group of amino acids can react with alcohol, in the presence of a strong acid catalyst (usually conc. sulfuric acid) under reflux to produce an ester and water
Reagents = Amino acid + Alcohol Conditions = Reflux Product(s) = Ester + Water
25
Give the generic equation in the reaction between an amino acid and alcohol
Amino acid + Alcohol → Ester + Water
26
Describe the reaction of the amine group of amino acids with acids
When an amino acid reacts with an acid, the product formed is a SALT of the CONJUGATE ACID.
In this reaction, the amino acid acts as a base an accepts the entire acid onto the amine group.
27
When an acid is added to an alpha amino acid, what happens to the COOH and the NH2 groups?
COOH stays the same
NH2 changes to NH3^+Z^-
Where Z is the group attached to the acid reactant
28
What is the functional group of amides?
RCON
29
What is a weak base, amines or amides?
Amides
30
How many types of amides can we get?
3
Primary, Secondary and Tertiary
*You don't need to know about tertiary amides
31
If we have a primary amide, how many hydrogen groups are attached to the nitrogen?
Also, how many R groups are attached to the nitrogen?
2 hydrogen groups
| 1 R group
32
If we have a secondary amide, how many hydrogen groups are attached to the nitrogen?
Also, how many R groups are attached to the nitrogen?
1 hydrogen group
| 2 R groups
33
How do we name primary amides?
```
Stem = Longest carbon chain (take off the e)
Ending = Amide
```
34
What is a chiral carbon?
A carbon atom which has 4 different groups attached to it.
35
What do chiral carbons lead to ?
The possibility of optical isomerism
36
What are optical isomers?
Mirror images of each other, where no matter which way you turn them, they cannot be superimposed. They only occur if there's a chiral carbon atom in a given molecule
37
What do optical isomers do?
| And in which directions?
Optical isomers rotate plane polarised light
One optical isomer rotates plane polarised light in a clockwise direction, whilst the other optical isomer rotates it in an anticlockwise direct
38
When rotating light, optical isomers rotate it in...
The opposite direction but by the SAME amount
39
What must you do when drawing optical isomers?
Draw 3D bonds
Draw the mirror line
Reflect the isomers (as in switch the left and right molecules around)
40
Can some molecules have more than one chiral centre?
YES!
41
How can we make a polyester?
Reacting a dicarboxylic acid with a diol forming ester links.
42
How can we represent an ester link?
R-COO-R'
R and R' can be the same aren't often.
43
Give the generic equation for the production of a polyester
Dicarboxylic acid + Diol → Polyester + Water
44
In the production of polyesters, what is the waste product and where do the bonds that contribute in the production it come from?
Waste product is water.
OH is lost from dicarboxylic acid
H is lost from diol
45
How can we make polyamides?
Reacting a dicarboxylic acid with a diamine forming amide links
46
How can we represent an amide link?
CONH
47
Give the generic equation for the production of a polyamide
Dicarboxylic acid + Diamine → Polyamide + Water
48
What is meant by hydrolysis?
The process of breaking down a compound through the use of water.
49
Because hydrolysis tends to be slow, we use an..
Acid or base
50
For polyesters, what is faster, acidic hydrolysis or basic hydrolysis?
Basic
51
For polyamides, what is faster, acidic hydrolysis or basic hydrolysis?
Acidic
→
52
If we hydrolyse a polyester under acidic conditions, what do we get?
An alcohol and a carboxylic acid
53
If we hydrolyse a polyester under basic conditions, what do we get?
An alcohol and a dicarboxylate salt
54
If we hydrolyse a polyamide under acidic conditions, what do we get?
A carboxylic acid and a di-salt of a diamine
55
If we hydrolyse a polyamide under basic conditions, what do we get?
A diamine and the salt of a dicarboxylic acid
56
Give the generic equation for the acidic hydrolysis of a polyester
Polyester + 2nH2O → Diol + Dicarboxylic acid
57
Give the generic equation for the basic hydrolysis of a polyester
Polyester + 2nNaOH → Diol + Dicarboxylate salt
58
Give the generic equation for the acidic hydrolysis of a polyamide
Polyamide + 2nH2O → Di-salt of amine + Dicarboxylic acid
59
Give the generic equation for the basic hydrolysis of a polyamide
Polyamide + 2nNaOH → Diamine + Dicarboxylate salt
60
How can we find the repeat unit from a given monomer for addition polymerisation?
Replace the double bond with a single bond
Add a bond to each carbon, brackets and a n
Repeat the monomer
61
How can we find a repeat unit for a polyamide?
1) Draw the monomers next to each other
2) Remove an OH from the dicarboxylic acid and an H from the diamine
3) Join the C from the dicarboxylic acid with the N from the diamine to form an amide link
4) Take another OH and H off the ends of the moluecle
5) Draw brackets around it, and then there is your repeat unit
62
How can we find a repeat unit for a polyester?
1) Draw the monomers next to each other
2) Remove an OH from the dicarboxylic acid and an H from the diol
3) Join the C from the dicarboxylic acid with the O from the diol to form an esterlink
4) Take another OH and H off the ends of the moluecle
5) Draw brackets around it, and then there is your repeat unit
63
How do you find monomers from an addition polymerisation polymer chain?
Find repeat unit
Remove empty bonds
Replace the central carbon bond [C-C] with [C=C]
64
How do you find monomers from an condensation polymer chain?
Find the amide (HN-CO) or ester (CO-O) link and break it down the middle
Then add an H or an OH to bond ends of both molecules depending on what the groups at the end are
Add Hs to O's or N's
Add OH groups to carbon atoms
65
What is a nucleophile?
An electron pair donor
66
What is an electrophile?
An electron pair acceptor
67
What is meant by nucleophilic substitution?
A reaction where a nucleophilic atom is subbed for another species.
68
What is meant by nucleophilic addition?
A reaction where a nucleophile is added to a compound
69
Is Cyanide an electrophile or nucleophile?
Nucleophile
70
Describe the formation of CCN- by reaction of haloalkanes with CN
Reaction type = Nucleophilic substitution
Reagents = Haloalkane + Ethanol + KCN/NaCN
Conditions = Reflux
Products = Nitrile + Halogen ion
71
Give the generic equation for the formation of CCN- by reaction of haloalkanes with CN
RX + CN^- → R-C≡N + X^-
72
In the formation of CCN- by reaction of haloalkanes with CN, why do we use ethanol rather than water?
If we use water, OH^- may act as the nucleophile rather than CN^- and so the carbon chain length will not increase.
73
Describe the formation of CCN- by reaction of carbonyl compounds with HCN
Reaction type = Nucleophilic addition
Reagents = Carbonyl compound + HCN
Conditions =
Products = Hydroxynitrile
74
When referring to reactions, we must always talk about .....
```
Dipoles
Charges
Curly arrows
Conditions
Product
Mechanism (if required)
```
75
Why are nitriles useful?
Nitriles are useful because they can be converted into new functional groups. This is because the nitrile froup is very reactive.
76
Give the 2 methods in which a nitrile could be reduced
Method 1
Using lithium aluminium hydride (LiAlH4) followed by some dilute acid.
Method 2 (Catalytic hydrogenation)
Using Hydrogen + Nickel cataltyst
77
Give a generic equation for when a nitrile is reduced via LiAlH4 followed by dilute acid
RCH2C≡N + 4[H] → RCHCH2NH2
78
Give a generic equation for when a nitrile is reduced via hydrogen and a nickel catalyst
RCH2C≡N + 2H2 → RCHCH2NH2
79
Give all the details of the reduction of nitriles using H2 and a nickel catalyst
Reaction name = Catalytic hydrogenation
Reagents = H2 and a Nickel Catalyst
Conditions = High temperature and pressure
Product = Primary amine
80
When a nitrile is reduced, what is formed?
A primary amine
81
Describe the reaction of nitriles by acidichydrolysis
If you reflux a nitrile with HCl, then the nitrile group hydrolyses to form a carboxylic acid. The other product is ammonium chloride.
```
Reagents = Nitrile + HCl + H2O
Conditions = Reflux
Products = Carboxylic acid and ammonium chloride
```
82
Give a generic equation for when a nitrile is hydrolysed under acidic conditions
RCH2C≡N + HCl + 2H2O → RCH2COOH + NH4Cl
83
What is meant by Friedel-Crafts alkylation?
A reaction where any alkyl group is put onto a benzene ring using a haloalkane and a halogen carrier under anhydrous conditions. The resultant product is an alkylbenzene.
84
Give the general equation for Friedel- Crafts alkylation
C6H6 + R-X → C6H5R + HX
(Benzene) + (Haloalkane) → Alkylbenzene + Hydrogen halide
Conditions: Reflux and a halogen carrier
85
Give all the details of a Friedel-Crafts alkylation reaction
Reagents : A haloalkane and an anhydrous halogen carrier (catalyst)
Conditions: Reflux in the presence of an anhydrous halogen carrier. (CATALYST)
Products: Alkylbenzene + Hydrogen halide.
Generation of electrophile :RX + FeX3 → R^+ + FeX4^-
Regeneration of catalyst : H^+ + FeX4^- → FeX3 + HX
86
Give the general equation for the generation of the electrophile in a alkylation reaction
RX + FeX3 → R^+ + FeX4^-
87
Give the general equation for the regeneration of the catalyst for alkylation
H^+ + FeX4^- → FeX3 + HX
88
What is meant by Friedel-Crafts acylation?
A reaction where any acyl group is put onto a benzene ring using an acyl chloride and an halogen carrier under anhydrous conditions. The resultant product is an phenylketone + HCl.
89
Give the general equation for Friedel- Crafts acylation
C6H6 + RCOCl → C6H5COR + HCl
| Benzene) + (Acyl Chloride) → (Phenylketone) + (HCl
90
Give all the details of a Friedel-Crafts acylation reaction
Reagents : An acyl chloride and an anhydrous halogen carrier
Conditions: Reflux in the presence of an anhydrous halogen carrier. (CATALYST)
Products: Phenylketone + Hydrochloric acid
Electrophile: NO2+
Generation of electrophile: RCOCl + FeCl3 → FeCl4^- + R^+CO
Regeneration of catalyst : H+ + FeCl4^- → FeCl3 + HCl
91
Give the general equation for the generation of the electrophile in a acylation reaction
RCOCl + FeCl3 → FeCl4^- + R^+CO
92
Give the general equation for the regeneration of the catalyst for acylation
H+ + FeCl4^- → FeCl3 + HCl
93
Why do we use reflux?
To ensure that we don't lose any volatile organic substances. This is because reflux prevents the evaporation of reagents
94
Why do we use distillaion?
To separate substances with difference boiling points
95
How does distillation work?
Distillation works by gently heating a mixture of substances. These substances will evaporate out in ORDER of increasing boiling point.
If you know the boiling point of your pure product, you can use a thermometer to know where in will evaporate.
96
What do we use filtration under reduced pressure to do?
Separate liquid impurities from solids
97
Give the process of filtration under reduced pressure
Step 1) Connect thick-walled rubber tubing to vacuum source
Step 2) Place Buchner/Hirsch funnel on top of the filter flask
Step 3) Connect tubing with the vacuum source to the side arm of the filter flask and start suction
Step 4) Put a piece of filter paper in the funnel (just enough to cover the holes)
Step 5) Using the solvent (e.g. distilled water), wet the paper so it sticks over all holes
Step 6) Pour reaction mixture into the funnel
Step 7) Wash out the piece of equipment which contained the reaction mixture using a solvent over the funnel (Done to collect as much product as possible)
Step 8) Rinse the solid on the filter paper with more solvent
Step 9) Wait for some time and then turn off the suction
Step 10) Tip contents of the funnel onto a watch glass
98
What do we use crystallisation to do?
| BENZOIC ACID PAG
Purify impure solids
99
Give the process of recrystallisatio
Step 1) Dissolve the impure solid in a minimum amont of hot solvent possible and filter
Step 2) Cool solution by putting the filtrate in an ince bath
Step 3) Collect purified product using vacuum filtrate
Step 4) Wash with cold solvent/water and dry
100
Why do we measure melting points?
To test for purity.
101
Give the process of measuring melting points
Step 1) Place a few grains of organic product in a capillary tube
Step 2) Insert the tube into a MP machine with a thermometer with a suitable range,
Step 3) Turn on the machine and set the dial to 4
Step 4) Note the temperature when the crystals start to melt and when they are full liquidised
