Isobenzane
Structural formula | |||||||||||||||||||
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General | |||||||||||||||||||
Surname | Isobenzane | ||||||||||||||||||
other names |
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Molecular formula | C 9 H 4 Cl 8 O | ||||||||||||||||||
Brief description |
white solid |
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properties | |||||||||||||||||||
Molar mass | 411.73 g mol −1 | ||||||||||||||||||
Physical state |
firmly |
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density |
1.87 g cm −3 |
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Melting point |
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boiling point |
> 210 ° C (decomposition) |
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Vapor pressure |
0.39 mPa (20 ° C) |
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solubility | |||||||||||||||||||
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Toxicological data | |||||||||||||||||||
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions . |
Isobenzane (Telodrin) is a highly toxic organochlorine compound that has an insecticidal effect. It was only made between 1958 and 1965. Use has been discontinued. It is a persistent organic pollutant that can remain in the soil for 2 to 7 years. The biological half-life of isobenzane in human blood is estimated to be around 2.8 years.
Presentation and extraction
The precursor 4,5,6,7,10,10-hexachloro-4,7-endomethylene-4,7,8,9-tetrahydrophthalane can be obtained by two synthetic routes. In a synthesis variant published in 1954, the 1,4,5,6,7,7-hexachloro-2,3-bishydroxymethylbicyclo [ 2, 2 ] is first obtained by reacting hexachlorocyclopentadiene with cis-1,4-dihydroxybut-2-ene . 2,1 ] hept-5-ene, which is then dehydrated to the precursor. In 1961, a direct preparation of the precursor via a Diels-Alder reaction with hexachlorocyclopentadiene and 2,5-dihydrofuran was found. The target compound is then synthesized by photochlorination of the precursor.
properties
Isobenzane forms colorless crystals that melt at 122.2 ° C. The enthalpy of fusion is 26.8 kJ mol −1 . The stereochemistry was examined by means of 1 H-NMR spectroscopy and X-ray diffractometry , as well as an oxidative degradation. It could be shown here that the compound can be classified as exo-1, exo-3,4,5,6,7,8,8-octachloro-1,3,3a, 4,7,7a-hexahydro-endo-4,7 -methanoisobenzofuran is present. The compound crystallizes in a monoclinic crystal lattice with the space group C2 / c.
Individual evidence
- ↑ a b c d Environmental Health Criteria (EHC) for isobenzane , accessed December 22, 2017.
- ↑ a b c d e f g h i Entry on isobenzane in the GESTIS substance database of the IFA , accessed on December 22, 2017 (JavaScript required)
- ↑ a b c Plato, C .; Glasgow, AR, Jr .: Differential scanning calorimetry as a general method for determining the purity and heat of fusion of high-purity organic chemicals. Application to 95 compounds in Anal. Chem. 41 (1969) 330-336, doi : 10.1021 / ac60271a041 .
- ↑ a b c David R. Lide (Ed.): CRC Handbook of Chemistry and Physics . 97th edition. (Internet version: 2016), CRC Press / Taylor and Francis, Boca Raton, FL, Physical Constants of Organic Compound, pp. 3-326 - 3-327.
- ↑ a b R.L. Metcalf: Insect Control , in: Ullmanns Enzyklopädie der Technischen Chemie , Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim 2012; doi : 10.1002 / 14356007.a14_263 .
- ↑ Entry on isobenzane in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on December 28, 2017. Manufacturers or distributors can expand the harmonized classification and labeling .
- ↑ Patent DE15324 (Ruhrchemie AG 1954).
- ↑ a b Patent US3000907 (Ruhrchemie AG 1961).
- ↑ Riemschneider, R .; Gallert, H .; Andres, P: Zur Chemie von Polyhalocyclopentadienes, 22. Mitt .: About the production of 1,4,5,6,7,7-Hexachlorbicyclo [2.2.1] hepten- (5) -bishydroxymethylene- (2,3) in Monthly Chem. 92 (1961) 1075-1079, doi : 10.1007 / BF00924776 .
- ↑ Patent DE1020346 (Ruhrchemie AG 1954).
- ↑ Feichtinger, H .; Linden, H.-W .: Telodrin, Its Synthesis and Derivatives in Chem. Ind. 79 (1965) 1938-1940.
- ↑ Feichtinger, H .; Linden, H.-W .: Friedel-Crafts reactions of 1-substituted 4.5.6.7.10.10-hexachloro-4.7-methylene-4.7.8.9-tetrahydrophthalane in Chem. Ber. 97 (1964) 2779-2784, doi : 10.1002 / cber.19640971009 .
- ^ Singer, H .; Ballschmiter, K .: H-NMR spectroscopic investigations on 1.3-disubstituted derivatives of 4.5.6.7.8.8-hexachloro-1.3.3a.4.7.7a-hexahydro-4.7-methano-isobenzofurans in Chem. Ber. 101 (1968) 17-23, doi : 10.1002 / cber.19681010104 .
- ↑ a b Feichtinger, H .; Linden, H.-W .; Singer, H .: On the knowledge of halogenated 4.7.8.9-tetrahydro-4.7-methano-phthalanes, IV. On the configuration of 1.3-disubstituted 4.5.6.7.10.10-hexachloro-4.7.8.9-tetrahydro-4.7-methano-phthalanes in Chem. Ber. 101 (1968) 2776-2784, doi : 10.1002 / cber.19681010823 .
- ↑ a b Smith, G .; Kennard, GHL: Insecticides. XIII. Crystal structure of isobenzane (exo-1, exo-3,4,5,6,7,8,8-octachloro-1,3,3a, 4,7,7a-hexahydro-endo-4,7-methanoisobenzofuran) in Austr. J. Chem. 30 (1977) 1117-1122, doi : 10.1071 / CH9771117 .