Years' experience of reading A level scripts and of teaching practical organic chemistry have shown that many people can quote reaction conditions or reproduce procedures, yet when asked why things are done have not the least idea. The accompanying recipes (for that is what practical instructions really are) are designed to help to overcome this – the reasons for each step are explained.

Two important cautions:

            These pages are not intended as worksheets; the conversion into a list of instructions is to make the presentation workable for this purpose only. If the preparations are to be performed the original text or its equivalent must be consulted and a proper risk assessment made by the institution.

             All of these preparations are mentioned somewhere in the AS/A2 Edexcel syllabus; not all are intended to be performed. In particular preparations 6 – 9 are unsuitable for school use because of the hazards presented; nonetheless an understanding of them is expected. Experiment 11 is not suitable for execution by anyone other than a trained chemist.

            The recipes are adapted from Mann FG and Saunders BC, Practical Organic Chemistry', 4th edition, Longman, 1960.

 
The recipes:

 

1

Ethene from ethanol by dehydration with hot concentrated sulphuric acid.
 

2

1-bromobutane from butan-1-ol using sodium bromide and 50% sulphuric acid.
 

3

Iodoethane from ethanol using moist red phosphorus and iodine
 

4

Ethanal from ethanol by oxidation with potassium dichromate(VI) in sulphuric acid.
 

5

Ethyl ethanoate from ethanol and ethanoic acid.
 

6 

A lithium aluminium hydride reduction: (2-hydroxyphenyl)-methanol from 2-hydroxybenzoic acid.
 

7

The Hofmann Primary Amine Synthesis: methylamine from ethanamide.
 

8

Nitrobenzene from benzene using a mixture of concentrated nitric and sulphuric acids.
 

9

Phenylamine from nitrobenzene using tin and hydrochloric acid.
 

10

Diazotisation of phenylamine using sodium nitrite and concentrated hydrochloric acid.
  11 A Grignard reagent used for the preparation of 2-methylhexan-2-ol

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