An introduction to AS Level organic chemistry

You will be able to

• Describe the mechanisms of free-radical substitution, electrophilic addition and nucleophilic substitution using curly arrows that begin at a bond or a lone pair.
• Identify the intermediate (a carbocation or a transition state) and the products formed in each step of a mechanism.
• Explain why the more stable carbocation gives the major product of electrophilic addition to propene (Markovnikov addition).

You will be able to

• Deduce the possible structural isomers (chain, positional and functional group) of a molecule of known molecular formula and name them.
• Identify cis-trans isomerism in an alkene and explain its origin in terms of restricted rotation about the C=C bond.
• Identify a chiral centre in a molecule from its structural formula and state that it gives two optical isomers.