General Organic Chemistry (GOC) is the foundation of understanding organic chemistry. Here's a concise revision sheet to help you grasp the key concepts:
Electronic Effects
- Inductive Effect: The unequal sharing of electrons between atoms in a covalent bond due to electronegativity differences.
- -I effect: Electron-withdrawing effect (e.g., -NO2, -CN)
- +I effect: Electron-donating effect (e.g., -CH3, -NH2)
- Mesomeric Effect: The delocalization of electrons in a conjugated system.
- -M effect: Electron-withdrawing effect (e.g., -NO2, -C=O)
- +M effect: Electron-donating effect (e.g., -OH, -NH2)
- Hyperconjugation: The delocalization of sigma electrons adjacent to a pi bond.
Isomerism
- Structural Isomerism: Same molecular formula but different connectivity of atoms.
- Chain isomerism
- Position isomerism
- Functional group isomerism
- Stereoisomerism: Same molecular formula and connectivity but different spatial arrangement of atoms.
- Geometrical isomerism (cis-trans)
- Optical isomerism (enantiomers and diastereomers)
Aromaticity
- Hückel's Rule: A molecule is aromatic if it has (4n+2) pi electrons (where n is an integer).
- Benzene: The most common aromatic compound with six pi electrons.
Nucleophiles and Electrophiles
- Nucleophiles: Species that donate electron pairs (e.g., OH-, NH3).
- Electrophiles: Species that accept electron pairs (e.g., H+, CH3+).
Reactions
- Substitution Reactions: One atom or group is replaced by another.
- Electrophilic substitution (e.g., halogenation of benzene)
- Nucleophilic substitution (e.g., SN1 and SN2 reactions)
- Addition Reactions: Two or more molecules combine to form a larger molecule.
- Electrophilic addition (e.g., addition of HBr to alkenes)
- Nucleophilic addition (e.g., addition of Grignard reagents to carbonyl compounds)
- Elimination Reactions: A small molecule (e.g., H2O, HCl) is removed from a larger molecule.
- E1 and E2 reactions
Remember: Practice solving problems and understanding reaction mechanisms to reinforce your GOC knowledge.
