CH4 Revision (Organic Compounds containing oxygen)

This is one of the biggest topics in CH4, these notes cover the basic knowledge needed for the questions that could be asked in this topic.

HideShow resource information
CH3CH2CH2Br + NaOH -- CH3CH2CH2OH + NaBr
Nucleophilic substitution
1 of 35
Does a halogenobenzene react with NaOH to form an alcohol?
Yes, but they do not react readily, the conditions need to be very extreme in order to overcome the stability the benzene shows. For example it is very hard to form Phenol from Chlorobenzene.
2 of 35
Reducing agents?
Sodium tetrahydriodoborate (III) or Lithium tetrahydriodoaluminate (III) dissolved in ether.
3 of 35
What reaction is Aldehyde or Ketone to alcohol?
Reduction reaction.
4 of 35
Primary or Secondary alcohol + acid chloride
Ester + HCl
5 of 35
Primary or Secondary alcohol + Carboxylic acid (sulfuric acid catalyst & refluxed)
Ester + Water
6 of 35
Dehydration of Alcohols
To do this the alcohol is either heated and the vapor passed over an aluminium oxide catalyst, or is heated with a mixture of an excess of concentrated sulfuric or phosphoric acids.
7 of 35
Oxidation of primary alcohol
Primary alcohol -- Aldehyde -- Carboxylic acid
8 of 35
Oxidation of secondary alcohol
Secondary alcohol -- ketone
9 of 35
Common oxidizing agents
Acidified potassium dichroWillmate or Acidified Potassium manganate (VII)
10 of 35
Acidified Potassium dichromate colour change
Orange to green
11 of 35
Acidified Potassium manganate (VII) colour change
Purple to colourless
12 of 35
How do you test for an aldehyde or ketone?
2,4-DNPH (Bright orange ppt. for positive result)
13 of 35
Is phenol acidic?
The O-H bond on phenol is weak, this means in aqueous solution phenol is acidic, as you lose a proton and therefore form an phenoxide ion.
14 of 35
Testing for a phenol?
FeCl3(aq) and the positive result is a purple solution, this is not given for aliphatic alcohols.
15 of 35
Is phenol more susceptible to electrophilic substitution than benzene?
Yes, especially in the position 2, 4 and 6.
16 of 35
Phenol + Bromine water
2,4,6-tribromophenol (white ppt.)
17 of 35
How to identify an aldehyde?
Tollens reagent will give a silver mirror effect and Fehling's solution will give a red / brown ppt.
18 of 35
Tollens Reagent
Aqueous ammonia + silver nitrate until the brown ppt. just dissolves. [The aldehyde acts as a reducing agent]
19 of 35
Fehling's Reagent
Copper (II) + sodium hydroxide [The aldehyde acts a reducing agent]
20 of 35
Will a ketone reduce acidified dichromate?
No, an aldehyde however will.
21 of 35
Iodoform test?
CH3C=0 will react with an alkaline solution of iodine to form triodomethane, which is a yellow ppt.
22 of 35
The reaction of hydrogen cyanide with carbonyl compounds?
This is a way of ascending the homologous series (increasing carbon chain length). The nirile group can then be oxidized to form a more useful carboxylic acid.
23 of 35
Physical properties of carboxylic acids?
Boiling temperature increases with chain length and solubility deceases with chain length.
24 of 35
Why does solubility of carboxylic acids or alcohols decrease as the chain length increases?
This is because the O-H or -COOH functional group that is involved in the hydrogen bonding becomes a less significant part of the molecule, it therefore is less likely to hydrogen bond, which is key for it to be soluble.
25 of 35
List in order of strength, starting from weakest to strongest, the acidic nature Carboxylic acids, phenols, aliphatic alcohols and water
[weakest] Ethanol < Water < Phenol < Carboxylic acid [strongest]
26 of 35
Oxidation of primary alcohols
Primary alcohol -- Aldehyde -- Carboxylic acid
27 of 35
The oxidation of alkylbenzenes?
These can be oxidized with Purple potassium manganate (VII) solution. You will end up with a brown sludge which is manganese (IV) oxide. The mixture is then acidified with dilute acid to form white crystals of Benzene carboxylic acid.
28 of 35
What is decarboxylation?
The loss of a carboxyl group (C02), it leads to a reduction in the carbon chain.
29 of 35
The reduction of carboxylic acids
Lithium tetrahydriodoaluminate (III) dissolve in ethoxyethane is used. If the salt of the aromatic acid is used then an aromatic hydrocarbon is the organic product. This is a way of descending the homologous series [decreasing carbon chain length].
30 of 35
Forming acid chlorides (CH3COCl)
A carboxylic acid + phosphorus (V) chloride can be used to create an acid chloride. However if sulfur dichloride oxide is used the other products are gaseous so are easily removed from the reaction.
31 of 35
Acid Chloride + Alcohol
Ester + HCl
32 of 35
Acid Chloride + water
Carboxylic acid + HCl
33 of 35
Acid anhydrides
They are formed when acid chlorides react with salts of carboxylic acids.
34 of 35
Acid Anhydrides uses?
Ethanoic anhydride is used to make cellulose based polymers and in the production of aspirin.
35 of 35

Other cards in this set

Card 2

Front

Does a halogenobenzene react with NaOH to form an alcohol?

Back

Yes, but they do not react readily, the conditions need to be very extreme in order to overcome the stability the benzene shows. For example it is very hard to form Phenol from Chlorobenzene.

Card 3

Front

Reducing agents?

Back

Preview of the front of card 3

Card 4

Front

What reaction is Aldehyde or Ketone to alcohol?

Back

Preview of the front of card 4

Card 5

Front

Primary or Secondary alcohol + acid chloride

Back

Preview of the front of card 5
View more cards

Comments

No comments have yet been made

Similar Chemistry resources:

See all Chemistry resources »See all Organic compounds containing oxygen resources »