Beckmann Rearrangement: Oximes → Amides/Lactams (Anti Group Migrates!)

Master the Beckmann rearrangement: activating oximes, anti-migration rule, nitrilium intermediate, and hydrolysis to amides/lactams (e.g., caprolactam).

• Reaction: Oxime → amide (or lactam)
• What it does: Rearranges ketoximes to amides (ring expansion in cyclic cases)
• Typical reagents: Acid (H2SO4) or sulfonyl chloride activators
• Key intermediate: Nitrilium ion
• Driving force: Formation of stable amide after hydrolysis
• Exam type: Rearrangements
• Exam type: Stereospecificity