World Library  
Flag as Inappropriate
Email this Article

Hexachlorocyclopentadiene

Article Id: WHEBN0022929574
Reproduction Date:

Title: Hexachlorocyclopentadiene  
Author: World Heritage Encyclopedia
Language: English
Subject: Heptachlor, Inverse electron-demand Diels–Alder reaction, In situ chemical reduction, Empenthrin, Metofluthrin
Collection:
Publisher: World Heritage Encyclopedia
Publication
Date:
 

Hexachlorocyclopentadiene

Hexachlorocyclopentadiene
Skeletal formula Ball-and-stick model
Identifiers
CAS number  YesY
PubChem
ChemSpider  YesY
Jmol-3D images Image 1
Properties
Molecular formula C5Cl6
Molar mass 272.77 g mol−1
Appearance Pale-yellow to amber-colored liquid
Odor Pungent[1]
Density 1.702 g/cm3
Melting point −10 °C (14 °F; 263 K)
Boiling point 239 °C (462 °F; 512 K)
Vapor pressure 0.08 mmHg
Hazards
Main hazards Teratogen
Flash point 100 °C (212 °F; 373 K)
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
 YesY   YesY/N?)

Hexachlorocyclopentadiene, also known as C-56, is an [2]

Synthesis and applications

Hexachlorocyclopentadiene is prepared by chlorination of cyclopentadiene to give 1,1,2,3,4,5-octachlorocyclopentane, which in a second step undergoes dehydrochlorination:[3]

C5H6 + 6 Cl2 → C5H2Cl8 + 4 HCl
C5H2Cl8 → C5Cl6 + 2 HCl

Hexachlorocyclopentadiene readily undergoes the Diels-Alder reaction to give a variety of adducts that were commercialized as pesticides. The main derivatives are:

Additionally hexachlorocyclopentadiene is the precursor to the pesticides mirex and kepone, although these are not classified as cyclodienes.

Regulation

Almost all derivatives have been banned or are under consideration for banning, according to the deliberations of the Stockholm Convention on Persistent Organic Pollutants.

Insect resistance

In addition to regulatory pressures, these pesticides became less effective owing to genetic mutations of the targeted insects. The number of insects resistant to cyclodienes and lindane approached 300 by 1989.[2]

References

  1. ^ CDC - NIOSH Pocket Guide to Chemical Hazards
  2. ^ a b Robert L. Metcalf “Insect Control” in Ullmann’s Encyclopedia of Industrial Chemistry” Wiley-VCH, Wienheim, 2002. doi:10.1002/14356007.a14_263
  3. ^ Dieter Hönicke, Ringo Födisch, Peter Claus, Michael Olson “Cyclopentadiene and Cyclopentene” Ullmann's Encyclopedia of Industrial Chemistry 2002, Wiley-VCH, Weinheim. doi:10.1002/14356007.a08_227
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 USA.gov, which sources content from all federal, state, local, tribal, and territorial government publication portals (.gov, .mil, .edu). Funding for USA.gov 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 Project Gutenberg 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.