1. Aldehydes and Ketones  Functional group formula?  C=O  F.G. name?  The carbonyl group

2. Naming  Aldehydes – how can you spot one?  (C=O on the end of the chain i.e. C N o 1) end in  ……al  Ketones  (C=O has C’s on both sides) end in  ….one  Position of C=O given as a number  What is the largest chain where a number is not required?  Butanone – 4 C’s  Try 1,1,1-trifluoropentan-2-one  1-hydroxyhex-2-ene-4-one  Watch out for benzaldehyde and phenylethanone

3. Reduction of Aldehydes and Ketones to Alcohols  Reagents  NaBH 4 (sodium borohydride) – a source of hydride (H - ions) then dilute sulphuric acid  Conditions  Room temperature  Another source of H - ?  LiAlH 4

4. Equation  CH 3 CHO + 2[H]  CH 3 CH 2 OH  Draw a diagram showing how the reactants relate to the products  Repeat the equation and diagram for propanone  See questions page 17 of notes

5. How does it happen?  The mechanism shows this  What factors do you consider when trying to work out a mechanism?  Polarity of bonds  Areas of positive or negative charge  Characteristics of particles present in the reactants – NaBH 4 is a source of H -.

6. Reduction mechanism – addition of hydrogen

7. How does it happen?  Conditions – are free radicals likely to be formed?  KCN contains which particles?  K + and CN - (dot/cross diagram?)  What do acids do?  Try to create a mechanism (consider ethanal).  Check names of products and note that in all cases a 2-hydroxy compound is formed  See q’s page 18

8. Oxidation of Aldehydes  Remember that ketones are not readily oxidised  Extension note – ketones can be oxidised, but only under relatively severe conditions, where the carbon chain is broken.  They are flammable ( burning= oxidation)

9. Oxidation of Aldehydes  Reagents  K 2 Cr 2 O 7 / sulphuric acid  K 2 Cr 2 O 7 = potassium dichromate  Conditions  H&R  When do you heat and distil?

10. Oxidation of Aldehydes  Equation  RCHO + [O]  RCOOH  Draw a diagram to illustrate this (not a mechanism)  See Q,s page 20

11. Tests for Aldehydes/ketones  2,4-dinitrophenylhydrazine  Test for?  Carbonyl group C=O  Observation?  Orange precipitate