Nucleophilic substitution
What Nucleophilic substitution means in Chemistry A-Level, as defined for AQA, OCR.
Definitions of Nucleophilic substitution
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Reference: AQA
A one-step mechanism in which an arrow goes from the nitrogen lone pair to the δ⁺ carbon while an arrow goes from the carbon-halogen bond to the halogen, which leaves as a halide ion.
Ammonia or an amine acts as the nucleophile and attacks the electron-poor carbon of a haloalkane, displacing the halide ion.
A reaction in which the halogen atom of a haloalkane is replaced by a nucleophile and the carbon–halogen bond breaks.
A reaction in which a nucleophile replaces the halogen in a haloalkane, which leaves as a halide ion.
Topics that use Nucleophilic substitution
- Nucleophilic properties (A-level only) (AQA A-Level)
- Amines (OCR A-Level)
- Haloalkanes (OCR A-Level)
Related terms
- nucleophile
- addition-elimination
- amide formation
- anhydride versus acyl chloride
- attack at a δ⁺ carbon
- attraction to negative surfaces
- Bond enthalpy
- Bond strength and reactivity down Group 7
Using Nucleophilic substitution in the exam
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