Ortho, meta, and para Substitution
See also: Electrophilic aromatic substitution- In ortho-substitution, two substituents occupy positions next to each other, which may be numbered 1 and 2. In the diagram, these positions are marked R and ortho.
- In meta-substitution the substituents occupy positions 1 and 3 (corresponding to R and meta in the diagram).
- In para-substitution, the substituents occupy the opposite ends (positions 1 and 4, corresponding to R and para in the diagram). The toluidines serve as an example for these three types of substitution.
Read more about this topic: Arene Substitution Patterns
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