MD - MEDICINES BY DESIGN
Alcohols
Reactions for Synthesis 
Drugs as Medicines
Simple Synthetic Routes
Alkenes
Primary Alcohols
Halogenoalkanes
Carboxylic Acids
Amines
Arenes
Phenols
Derivatives of Carboxylic Acids
Simple Synthetic Routes
A common problem for an organic chemist is the synthesis of a compound of known structure. The starting point in planning a synthesis is to examine the required compound. This compound is called the target molecule. By looking at the functional groups it contains, chemists can work backwards, through a logical sequence of reactions, until suitable starting materials can be found. Several steps may be necessary, and a number of intermediates may have to be prepared and purified. In a more complex synthesis involving several steps, there will often be more than one possible route to the target molecule. A choice will need to be made. Before you embark on a synthesis it is necessary for you to know the main reactions of the functional groups. The following charts summarise the important reactions than have been covered in this course.
Alkenes
Simple alkenes such as ethene and propene are readily obtained by cracking petroleum fractions. The presence of the double bond causes them to be quite reactive. The example used is propene, CH3CH=CH2.
Apologies: this section has yet to be written!
Primary Alcohols
Ethanol will be used as a typical example of a primary alcohol.
Apologies: this section has yet to be written!
Halogenoalkanes
Bromoethane will be used as an example of a typical halogenoalkane.
Apologies: this section has yet to be written!
Carboxylic Acids
Ethanoic acid will be taken as a typical carboxylic acid.
Apologies: this section has yet to be written!
Amines
Ethylamine will be taken as a typical example of a primary amine.
Apologies: this section has yet to be written!
Arenes
Benzene will be taken as a typical example of an arene.
Phenols
Derivatives of Carboxylic Acids
Acyl Chlorides
Acyl chlorides have the functional group 
An example is ethanoyl chloride, CH3COCl. This is made by reacting ethanoic acid with phosphorus pentachloride.
CH3COCl + POCl3 +
HClAcyl chlorides are much more reactive than carboxylic acids. They readily undergo nucleophilic substitution when attacked by nucleophiles such as, H2O, NH3 and alcohols.
- Water. Ethanoyl chloride is hydrolysed by water producing ethanoic acid.
CH3COCl + H2O CH3CO2H + HCl - Ammonia. Ethanoyl chloride readily reacts with aqueous ammonia to produce an amide.
CH3COCl + NH3 CH3CONH2 + HCl ethanamide - Ethanol. Ethanoyl chloride rapidly reacts with alcohols to form esters.
CH3COCl + C2H5OH CH3CO2C2H5 + HCl ethyl ethanoate
Acid Anhydrides
Acid anhydrides are also acylating agents and react in the same way as acyl halides with water, ammonia and alcohols, although not quite so vigorously.
Acid anhydrides have the functional group: 
- Water. Ethanoic anhydride reacts with water to produce ethanoic acid.
(CH3CO)2O + H2O 2CH3CO2H - Ammonia. Anhydrides react with ammonia to form an amide.
(CH3CO)2O + NH3 CH3CONH2 + CH3CO2H ethanamide - Ethanol. Anhydrides react with alcohols to produce esters.
(CH3CO)2O + C2H5OH CH3CO2C2H5 + CH3CO2H ethyl ethanoate
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