The list of mechanisms to be learned for Class 12 Organic Chemistry boards 2024 is as follows:

Nucleophilic Substitution Reactions:

• SN1 Mechanism:
  • Tertiary alkyl halide
  • Carbocation intermediate
  • Rate-determining step: formation of carbocation
  • Stereochemistry: racemization
• SN2 Mechanism:
  • Primary and secondary alkyl halides
  • Backside attack
  • Inversion of configuration
  • Rate-determining step: nucleophilic attack

Elimination Reactions:

• E1 Mechanism:
  • Tertiary alkyl halide
  • Carbocation intermediate
  • Rate-determining step: formation of carbocation
  • Zaitsev's rule
• E2 Mechanism:
  • Primary, secondary, and tertiary alkyl halides
  • Strong base
  • Anti-periplanar arrangement
  • Zaitsev's rule

Addition Reactions:

• Electrophilic Addition to Alkenes:
  • Markovnikov's rule
  • Anti-addition
  • Examples: addition of HBr, H2SO4, Cl2, Br2
• Nucleophilic Addition to Carbonyl Compounds:
  • Addition of Grignard reagents, organolithium compounds, and hydride reagents
  • Formation of alcohols
• Addition of HCN to Carbonyl Compounds:
  • Formation of cyanohydrins

Rearrangements:

• Pinacol-Pinacolone Rearrangement:
  • Conversion of vicinal diols to ketones
• Claisen Rearrangement:
  • Rearrangement of allyl ethers
• Beckmann Rearrangement:
  • Conversion of oximes to amides

Aromatic Compounds:

• Electrophilic Aromatic Substitution:
  • Examples: nitration, sulfonation, halogenation, Friedel-Crafts acylation and alkylation