1.pd

1. © www.chemsheets.co.uk A2 1049 2-June-2016

2. ALDEHYDES
methanal
ethanal
propanal
3-methylbutanal
© www.chemsheets.co.uk A2 1049 2-June-2016

3. KETONES
propanone
butanone
pentan-3-one
4-methylpentan-2-one
© www.chemsheets.co.uk A2 1049 2-June-2016

4. OXIDATION & REDUCTION
© www.chemsheets.co.uk A2 1049 2-June-2016

5. • Tollen’s reagent, contains [Ag(NH3)2]+
• Used to test for aldehydes – gives silver mirror
• Reduced from Ag(+1) to Ag(0)
OXIDATION & REDUCTION

6. • Fehling’s solution, contains Cu(+2)
• Used to test for aldehydes – gives brick-red precipitate of Cu2O
• Reduced from Cu(+2) to Cu(+1)
OXIDATION & REDUCTION

7. • Acidified potassium dichromate, contains Cr2O7
2-
• Used to test for alcohols (1y and 2y) & aldehydes – goes from
orange Cr2O7
2- to green Cr3+
• Reduced from Cr(+6) to Cr(+3)
OXIDATION & REDUCTION

8. Distillation
OXIDATION & REDUCTION
Alcohols and carboxylic acids (have
hydrogen bonds between molecules)
have higher bpts than aldehydes – so
aldehyde can be distilled out as formed
Reflux
Aldehyde
condenses back
into reaction
mixture and
reacts further

9. NUCLEOPHILIC ADDITION
© www.chemsheets.co.uk A2 1049 2-June-2016
+ –
• Addition reactions: atoms add across C=O to the C and O
• C is + so attacked by nucleophiles (electron pair donors)
• The three atoms attached to the C are planar

10. © www.chemsheets.co.uk A2 1026 25-May-2016
Reduction with NaBH4
NUCLEOPHILIC ADDITION
+ 2[H]
H
_
:
H
_
:

11. © www.chemsheets.co.uk A2 1026 25-May-2016
e.g. ethanal + NaBH4
NUCLEOPHILIC ADDITION
+ 2[H]
H
_
:
H
_
:
+ 2[H]
H
_
:
H
_
:

12. © www.chemsheets.co.uk A2 1026 25-May-2016
e.g. propanone + NaBH4
NUCLEOPHILIC ADDITION
+ 2[H]
H
_
:
H
_
:
+ 2[H]
H
_
:
H
_
:

13. © www.chemsheets.co.uk A2 1026 25-May-2016
Reaction with KCN then acid
NUCLEOPHILIC ADDITION
+ HCN
CN
_
:
H
_
:

14. © www.chemsheets.co.uk A2 1026 25-May-2016
NUCLEOPHILIC ADDITION
CN
CN
_
_
:
:
• many hydroxynitriles contain chiral C
• formed as racemic mixture (50/50 mixture of enantiomers)
• as equal chance of attack from above & below plane

15. © www.chemsheets.co.uk A2 1026 25-May-2016
CN
CN
_
_
:
:

16. © www.chemsheets.co.uk A2 1026 25-May-2016
e.g. propanone + KCN then acid
NUCLEOPHILIC ADDITION
+ HCN
CN
_
:
H
_
:
+ HCN
CN
_
:
H
_
:

17. © www.chemsheets.co.uk A2 1026 25-May-2016
e.g. propanal + KCN then acid
NUCLEOPHILIC ADDITION
+ HCN
CN
_
:
H
_
:
+ HCN
CN
_
:
H
_
: