Lactam

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]

A lactam (the noun is a portmanteau of the words lactone + amide) is a cyclic amide. Prefixes may indicate the ring size: β-lactam (4-membered), γ-lactam (5-membered), δ-lactam (6-membered ring). That order in the nomenclature is because beta β, gamma γ and delta δ are the second, third and fourth letters in the alphabetical order of the Greek alphabet, respectively.

Synthesis[edit | edit source]

General synthetic methods exist for the organic synthesis of lactams.

• Lactams form by the acid-catalyzed rearrangement of oximes in the Beckmann rearrangement.
• Lactams form from cyclic ketones and ammonia in the Schmidt reaction.
• lactams form from cyclisation of amino acids.
• In iodolactamization ^[1] an iminium ion reacts with an halonium ion formed in situ by reaction of an alkene with iodine.

• Lactams form by copper catalyzed 1,3-dipolar cycloaddition of alkynes and nitrones in the Kinugasa reaction

Reactions[edit | edit source]

• Lactams can polymerize to polyamides.

See also[edit | edit source]

• β-lactam with a four-membered ring found in beta-lactam antibiotics. Penicillin, considered the most famous antibiotic, is a β-lactam antibiotic.
• Lactone, a cyclic ester.
• Caprolactam

References[edit | edit source]

External links[edit | edit source]

de:Lactame he:לקטם sv:Laktam Template:Jb1

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