Lactam

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

From left to right, general structures of a β-lactam, a γ-lactam and a δ-lactam.

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.

## Contents

* 1 Synthesis
* 2 Reactions
* 3 See also
* 4 References
* 5 External links

## 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]

1. ↑ Spencer Knapp, Frank S. Gibson Organic Syntheses, Coll. Vol. 9, p.516 (1998); Vol. 70, p.101 (1992) Online article

## External links

[edit | edit source]

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

Template:WS