CIP Priority Rules
AQA A-Level Chemistry
3.3.1
Identifying E/Z isomers requires us to determine which of the groups attached to each carbon of a double bond has the higher priority. Building on our understanding of stereoisomerism and E/Z isomerism, we can now introduce the CIP priority rules and apply them to identify and name different E/Z isomers. These rules provide a systematic approach that can be applied whenever we encounter E/Z isomerism later in the organic chemistry course.
In this topic you will:
- Know what the Cahn-Ingold-Prelog (CIP) priority rules are and why they are used.
- Be able to assign priority groups for each carbon atom of a carbon–carbon double bond using the CIP Priority Rules.
- Be able to identify whether an alkene is the E or Z isomer using the CIP priority rules.
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