This topic will cover the basic concepts of organic chemistry, including the definition of organic compounds, the structure of organic molecules, and the importance of carbon in organic chemistry.
Introduction to Organic Chemistry – Study Notes
| Concept | Key Points | Typical Examples |
|---|---|---|
| Carbon’s Bonding Ability | - Forms four covalent bonds (tetra‑valent). - Can make single, double, triple bonds and rings. - Hybridization: sp³ (tetrahedral), sp² (trigonal planar), sp (linear). |
Methane (sp³), ethene (sp²), acetylene (sp) |
| Functional Groups | Specific atom/group patterns that dictate reactivity. | Alcohol (‑OH), carbonyl (C=O), amine (‑NH₂), carboxyl (‑COOH), halide (‑X) |
| Isomerism | Same molecular formula, different structures. - Structural (constitutional) isomers: different connectivity. - Stereoisomers: same connectivity, different spatial arrangement (geometric, optical). |
Butanol (4 structural isomers), 2‑butanol vs. 2‑butene (geometric), (R)- and (S)-lactic acid (optical) |
| Nomenclature (IUPAC) | Systematic naming based on longest carbon chain, functional group priority, substituents, and numbering. | 3‑methyl‑2‑pentanol, 1‑chloro‑3‑butene |
| Reaction Types | - Addition (π‑bond breaks, new σ‑bonds form). - Elimination (σ‑bond breaks, π‑bond forms). - Substitution (one group replaces another). - Rearrangement (atoms shift within a molecule). |
Hydrogenation of alkenes, dehydration of alcohols, SN1/SN2 reactions, Claisen rearrangement |
| Mechanisms | Step‑by‑step electron flow illustrated with curved‑arrow notation. - Nucleophilic vs. electrophilic pathways. - Radical mechanisms involve unpaired electrons. |
SN2 (back‑side attack), electrophilic aromatic substitution, free‑radical halogenation |
| Class | General Formula / Feature | Representative Reactions |
|---|---|---|
| Alkanes | CₙH₂ₙ₊₂, saturated, sp³ C | Combustion, free‑radical halogenation |
| Alkenes | CₙH₂ₙ, one C=C double bond, sp² C | Hydrogenation, halogen addition, hydrohalogenation |
| Alkynes | CₙH₂ₙ₋₂, one C≡C triple bond, sp C | Hydrogenation (to alkenes/alkanes), nucleophilic addition |
| Aromatics | Conjugated cyclic π‑system (e.g., benzene) | Electrophilic aromatic substitution |
| Alcohols | R |