World Library  
Flag as Inappropriate
Email this Article


Article Id: WHEBN0000884896
Reproduction Date:

Title: Imide  
Author: World Heritage Encyclopedia
Language: English
Subject: Functional group, Moiety (chemistry), Carbonyl, Aldol reaction, LaRC-SI
Collection: Imides
Publisher: World Heritage Encyclopedia


A general linear imide functional group

In functional group consisting of two acyl groups bound to nitrogen.[1] These compounds are structurally related to acid anhydrides, although imides are less reactive. In terms of commercial applications, imides are best known as components of high-strength polymers.


  • Nomenclature 1
    • Imides in coordination chemistry 1.1
  • Properties 2
  • Occurrence and applications 3
  • Preparation 4
  • Reactions 5
  • References 6
  • External links 7


Most imides are cyclic compounds derived from carbodiimides have the formula RN=C=NR, they are unrelated to imides.

Imides in coordination chemistry

The ligand in coordination chemistry known as imide has the formula NR. An imide is an intermediate in nitrogen fixation by synthetic catalysts.


Being highly polar, imides exhibit good solubility in polar media. The N-H center for imides derived from ammonia is acidic and can participate in hydrogen bonding. Unlike the structurally related acid anhydrides, they resist hydrolysis and some can even be recrystallized from boiling water.

Occurrence and applications

Many high strength or electrically conductive polymers contain imide subunits, i.e., the polyimides. One example is Kapton where the repeat unit consists of two imide groups derived from aromatic tetracarboxylic acids.[2] Another example of polyimides is the polyglutarimide typically made from polymethylmethacrylate (PMMA) and ammonia or a primary amine by aminolysis and cyclization of the PMMA at high temperature and pressure, typically in an extruder. This technique is called reactive extrusion. A commercial polyglutarimide product based on the methylamine derivative of PMMA, called Kamax (TM), was produced by the Rohm and Haas company. The toughness of these materials reflects the rigidity of the imide functional group.

Interest in the bioactivity of imide-containing compounds was sparked by the early discovery of the high bioactivity of the Thalidomide, famous for its adverse effects, is one result of this research. A number of fungicides and herbicides contain the imide functionality. Examples include Captan, which has been phased out because of its carcinogenic properties, and Procymidone.[3]

Illustrative imides, from left: N-ethylmaleimide, a biochemical reagent; phthalimide, an industrial chemical intermediate; Captan, a controversial herbicide; thalidomide, a drug that once caused many birth defects; a subunit of Kapton, a high strength polymer used to make space suits.


Most common imides are prepared by heating dicarboxylic acids or their anhydrides and ammonia or primary amines. The result is a condensation reaction:[4]

(RCO)2O + R'NH2 → (RCO)2NR' + H2O

These reactions proceed via the intermediacy of amides. The intramolecular reaction of a carboxylic acid with an amide is far faster than the intermolecular reaction, which is rarely observed.

Certain imides can also be prepared in the isoimide-to-imide Mumm rearrangement.


For imides derived from ammonia, the N-H center is acidic. Thus, alkali metal salts of imides are well known, a well-known example being potassium phthalimide. These salts can be alkylated to give N-alkylimides, which in turn can be degraded to release the primary amine. Strong nucleophiles, such as potassium hydroxide or hydrazine are used in the release step.

The nitrogen in imides is not very basic, which allows it to form stable compounds with halogens. Treatment of imides with halogens and base gives the N-halo derivatives. Examples that are useful in organic synthesis.


  1. ^
  2. ^ Walter W. Wright and Michael Hallden-Abberton "Polyimides" in Ullmann's Encyclopedia of Industrial Chemistry, 2002, Wiley-VCH, Weinheim. doi:10.1002/14356007.a21_253
  3. ^ Peter Ackermann, Paul Margot, Franz Müller “Fungicides, Agricultural“ in Ullmann's Encyclopedia of Industrial Chemistry, 2002, Wiley-VCH, Weinheim. doi:10.1002/14356007.a12_085
  4. ^ Vincent Rodeschini, Nigel S. Simpkins, and Fengzhi Zhangi (2009). "Illustrative imide formation from amine and anhydride".  

External links

  • IUPAC: imides
This article was sourced from Creative Commons Attribution-ShareAlike License; additional terms may apply. World Heritage Encyclopedia content is assembled from numerous content providers, Open Access Publishing, and in compliance with The Fair Access to Science and Technology Research Act (FASTR), Wikimedia Foundation, Inc., Public Library of Science, The Encyclopedia of Life, Open Book Publishers (OBP), PubMed, U.S. National Library of Medicine, National Center for Biotechnology Information, U.S. National Library of Medicine, National Institutes of Health (NIH), U.S. Department of Health & Human Services, and, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for and content contributors is made possible from the U.S. Congress, E-Government Act of 2002.
Crowd sourced content that is contributed to World Heritage Encyclopedia is peer reviewed and edited by our editorial staff to ensure quality scholarly research articles.
By using this site, you agree to the Terms of Use and Privacy Policy. World Heritage Encyclopedia™ is a registered trademark of the World Public Library Association, a non-profit organization.

Copyright © World Library Foundation. All rights reserved. eBooks from Hawaii eBook Library are sponsored by the World Library Foundation,
a 501c(4) Member's Support Non-Profit Organization, and is NOT affiliated with any governmental agency or department.