Lesson 9 of 13 · 7 min
Types of organic reactions
NCERT § "Types of Organic Reactions and Mechanisms"
Warm vinegar's acetic acid with ethanol and a drop of concentrated sulphuric acid, and the sour smell turns into the sweet smell of nail-polish remover: ethyl ethanoate. The –OH of the acid has been swapped for –OC₂H₅. That swap is one of just four basic kinds of organic reaction.
The lesson in notes
In short
Substitution: an atom or group is replaced by another, as in the conversion of an alkyl halide to an alcohol.
Addition: a reagent adds across a multiple bond, as in the addition of hydrogen halides to alkenes.
Elimination: atoms or groups are removed from adjacent carbons to create a multiple bond, as in dehydrohalogenation.
Rearrangement: atoms or groups within a molecule shift to give a structural isomer.
Reaction mechanisms describe the sequence of steps, the intermediates and the electron movement; curved arrows show movement of an electron pair, and fish-hook (half-headed) arrows show movement of single electrons.