Class 11 organic is the grammar — Class 12 organic is the literature. You cannot read without learning grammar first.
Chapter Sequence (Do Not Skip Steps)
- 1.Basic Principles of Organic Chemistry: nomenclature, isomerism, reaction intermediates
- 2.Hydrocarbons: alkanes, alkenes, alkynes, benzene
- 3.Only then: Class 12 organic chapters
IUPAC Nomenclature: The 5-Step Method
- 1.Find the longest carbon chain — this is the parent chain
- 2.Number the chain to give the first substituent the lowest number
- 3.Identify and name all substituents
- 4.List substituents alphabetically before the parent name
- 5.Add prefixes (di, tri) for multiple identical substituents
Types of Isomerism
- Chain isomerism: same molecular formula, different carbon skeleton
- Position isomerism: same functional group, different position on chain
- Functional group isomerism: same formula, different functional groups
- Geometrical isomerism: possible only with restricted rotation (double bond or ring)
Hydrocarbons: Key Reactions by Type
| Type | Key Reactions |
|---|---|
| Alkanes | Halogenation (free radical mechanism), combustion |
| Alkenes | Addition: HX (Markovnikov), H2 (catalytic), H2O (acid), KMnO4 |
| Alkynes | Addition reactions, acidic nature of terminal alkynes |
| Benzene | Electrophilic substitution: nitration, sulfonation, halogenation, Friedel-Crafts |
Tip
Markovnikov rule is asked every year: the negative part of an unsymmetrical reagent adds to the carbon with fewer hydrogens. Practise applying this to 5 different reactions until it is automatic.