Edexcel A Level Chemistry Revision Guide: Organic Chemistry

Organic chemistry is a major component of Edexcel A Level Chemistry. This comprehensive revision guide covers functional groups, reaction mechanisms, synthesis strategies, and analysis techniques, providing everything you need to master organic chemistry.

Functional Groups

Alkanes

• General formula: CnH2n+2
• Saturated hydrocarbons
• Combustion and substitution reactions
• Uses: fuels, solvents

Alkenes

• General formula: CnH2n
• Unsaturated hydrocarbons
• Addition reactions
• Polymerization

Alcohols

• Functional group: -OH
• Primary, secondary, tertiary
• Oxidation to aldehydes/ketones/carboxylic acids
• Esterification

Aldehydes and Ketones

• Aldehydes: -CHO
• Ketones: -CO-
• Reduction to alcohols
• Nucleophilic addition
• Tests: Fehling’s, Tollens’

Carboxylic Acids

• Functional group: -COOH
• Weak acids
• Esterification
• Reduction to alcohols

Amines

• Functional group: -NH2
• Basic properties
• Formation from halogenoalkanes
• Uses: dyes, drugs

Reaction Mechanisms

Nucleophilic Substitution

• SN1: two-step, carbocation intermediate
• SN2: one-step, inversion of configuration
• Factors affecting: substrate, nucleophile, solvent
• Curly arrow notation

Electrophilic Addition

• Alkenes react with electrophiles
• Mechanism: electrophile attacks double bond
• Examples: addition of HBr, Br2
• Markownikoff’s rule

Elimination

• Forms alkenes from alcohols/halogenoalkanes
• E1 and E2 mechanisms
• Zaitsev’s rule
• Conditions: heat, concentrated acid/base

Aromatic Substitution

• Electrophilic substitution on benzene
• Mechanism: electrophile attacks ring
• Examples: nitration, halogenation, Friedel-Crafts
• Directing effects of substituents

Synthesis

Multi-Step Synthesis

• Planning retrosynthetically
• Choosing appropriate reagents
• Protecting groups
• Yield optimization

Key Transformations

• Alcohols to aldehydes/ketones/carboxylic acids
• Halogenoalkanes to alcohols/amines
• Alkenes to alcohols
• Carboxylic acids to esters/amides

Analysis

IR Spectroscopy

• Functional group identification
• Key peaks: O-H, C=O, C-O, N-H
• Fingerprint region
• Interpretation

Mass Spectrometry

• Molecular ion peak
• Fragmentation patterns
• Isotope peaks
• Structure determination

NMR Spectroscopy

• 1H NMR: chemical shifts, integration, splitting
• 13C NMR: chemical shifts
• Interpretation
• Structure determination

Exam Tips

1. Know Your Mechanisms

• Practice drawing mechanisms
• Understand electron movement
• Learn key steps
• Apply to new reactions

2. Master Nomenclature

• Learn IUPAC rules
• Practice naming compounds
• Draw structures from names
• Check carefully

3. Practice Synthesis

• Plan retrosynthetically
• Know key transformations
• Choose appropriate reagents
• Consider protecting groups

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Use this revision guide as part of your comprehensive exam preparation. Combine with past paper practice and expert tutoring for best results.