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Isobenzan

From Wikipedia, the free encyclopedia
Isobenzan[1][2]
Names
IUPAC name
1,3,4,5,6,7,8,8-Octachloro-1,3,3a,4,7,7a-hexahydro-4,7-methanoisobenzofuran
Other names
Telodrin; 1,3,4,5,6,7,8,8-Octachloro-4,7-methylene-3a,4,7,7a-tetrahydro-isobenzofuran
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
ECHA InfoCard 100.005.497 Edit this at Wikidata
EC Number
  • 206-045-4
KEGG
RTECS number
  • PC1225000
UNII
UN number 2761
  • InChI=1S/C9H4Cl8O/c10-3-4(11)8(15)2-1(5(12)18-6(2)13)7(3,14)9(8,16)17/h1-2,5-6H
    Key: LRWHHSXTGZSMSN-UHFFFAOYSA-N
  • ClC1C2C3(Cl)C(Cl)=C(Cl)C(C3(Cl)Cl)(Cl)C2C(Cl)O1
Properties
C9H4Cl8O
Molar mass 411.73 g·mol−1
Appearance Whitish to light brown crystalline powder
Density 1.87 g/cm3
Melting point 121.3 °C (250.3 °F; 394.4 K)
Practically insoluble
Hazards
GHS labelling:
GHS06: ToxicGHS08: Health hazardGHS09: Environmental hazard
Danger
H300, H310, H320, H361, H370, H372, H410
P201, P202, P260, P262, P264, P270, P273, P280, P281, P301+P310, P302+P350, P305+P351+P338, P307+P311, P308+P313, P310, P314, P321, P322, P330, P337+P313, P361, P363, P391, P405, P501
NFPA 704 (fire diamond)
NFPA 704 four-colored diamondHealth 4: Very short exposure could cause death or major residual injury. E.g. VX gasFlammability 0: Will not burn. E.g. waterInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
4
0
0
Flash point Non-flammable
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)

Isobenzan (telodrin) is a highly toxic organochloride insecticide. It was produced only in the period from 1958 to 1965 and its use has been since discontinued.[1] It is a persistent organic pollutant that can remain in soil for 2 to 7 years, and the biological half-life of isobenzan in human blood is estimated to be about 2.8 years.[1]

It is classified as an extremely hazardous substance in the United States as defined in Section 302 of the U.S. Emergency Planning and Community Right-to-Know Act (42 U.S.C. 11002), and is subject to strict reporting requirements by facilities which produce, store, or use it in significant quantities.[3]

Production

[edit]

The precursor 4,5,6,7,10,10-hexachloro-4,7-endomethylene-4,7,8,9-tetrahydrophthalane can be obtained in two synthetic routes. In a synthesis method report published in 1954, 1,4,5,6,7,7-hexachloro-2,3-bishydroxymethylbicyclo[2,2,1]hept-5-ene is obtained, which is then dehydrated to the precursor.[4] In 1961, a direct preparation of the precursor via a Diels-Alder reaction with hexachlorocyclopentadiene and 2,5-Dihydrofuran was found.[5] The target compound is then synthesized by photochlorination of the precursor.[6][4][7][8]

References

[edit]
  1. ^ a b c Isobenzan, International Programme on Chemical Safety
  2. ^ Isobenzan at Sigma-Aldrich (dead link 3 March 2024)
  3. ^ 40 C.F.R.: Appendix A to Part 355—The List of Extremely Hazardous Substances and Their Threshold Planning Quantities (PDF) (Report) (July 1, 2008 ed.). Government Printing Office. Archived from the original (PDF) on February 25, 2012. Retrieved October 29, 2011.
  4. ^ a b US3000907A, Hans, Feichtinger; Hans, Tummes & Siegfried, Puschhof, "Chlorinated 4,5,6,7,10,10-hexachloro-4,7-endomethylene - 4,7,8,9 - tetrahydrophthalane insecticides", issued 1961-09-19 
  5. ^ Riemschneider, R.; Gallert, H.; Andres, P. (1961). "Zur Chemie von Polyhalocyclopentadienen, 22. Mitt.: Über die Herstellung von 1,4,5,6,7,7-Hexachlorbicyclo[2.2.1]hepten-(5)-bishydroxymethylen-(2,3)". Monatshefte für Chemie (in German). 92 (5): 1075–1079. doi:10.1007/BF00924776.
  6. ^ DE1020346B, Feichtinger, Dr Hans; Tummes, Dr Hans & Puschhof, Siegfried, "Insecticides and processes for their manufacture", issued 1957-12-05 
  7. ^ Feichtinger, H.; Linden, H. W. (1965). "Telodrin, its synthesis and derivatives". Chemistry & Industry. 47: 1938–1940. PMID 5846097.
  8. ^ Feichtinger, H.; Linden, H.-W.: Friedel-Crafts-Reaktionen 1-substituierter 4.5.6.7.10.10-Hexachlor-4.7-methylen-4.7.8.9-tetrahydro-phthalane in Chem. Ber. 97 (1964) 2779–2784, doi:10.1002/cber.19640971009.