dieldrin

Dieldrin
IUPAC name	(1aR,2R,2aS,3S,6R,6aR,7S,7aS)-3,4,5,6,9,9-hexachloro-1a,2,2a,3,6,6a,7,7a-octahydro-2,7:3,6-dimethanonaphtho[2,3-b]oxirene
Other names	Dieldrin
Identifiers
CAS number	60-57-1 Y
SMILES	ClC1=C(Cl)[C@@]5(Cl)C(Cl)(Cl)[C@]1(Cl)[C@H]4[C@H]3C[C@H]([C@@H]2O[C@@H]23)[C@H]45
Properties
Molecular formula	C12H8Cl6O
Molar mass	380.91 g mol−1
Density	1.75 g/cm³
Melting point	176-177 °C
Boiling point	385 °C
Hazards
MSDS	External MSDS
Y (what is this?)  (verify) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Dieldrin is a chlorinated hydrocarbon originally produced in 1948 by J. Hyman & Co, Denver, as an insecticide. The molecule has a ring structure based on naphthalene.

Dieldrin is closely related to aldrin which reacts further to form dieldrin. Aldrin is not toxic to insects, it is oxidised in the insect to form dieldrin which is the active compound. Both dieldrin and aldrin are named after the Diels-Alder reaction which is used to form aldrin from a mixture of norbornadiene and hexachlorocyclopentadiene.

Originally developed in the 1940s as an alternative to DDT, dieldrin proved to be a highly effective insecticide and was very widely used during the 1950s to early 1970s. Endrin is a stereoisomer of dieldrin.

However, it is an extremely persistent organic pollutant, it does not easily break down. Furthermore it tends to biomagnify as it is passed along the food chain. Long-term exposure has proven toxic to a very wide range of animals including humans, far greater than to the original insect targets. For this reason it is now banned in most of the world.

It has been linked to health problems such as Parkinson's, Breast Cancer, and immune, reproductive, and nervous system damage. It can also adversly affect testicular descent in the fetus if a pregnant woman is exposed to Dieldrin.

Synthesis

It can be formed from the synthesis of hexachloro-1,3-cyclopentadiene with norbornadiene in a Diels-Alder reaction, followed by epoxidation of the norbornene ring.^[1]

Synthesis of Dieldrin via a Diels-Alder reaction

See also

• Aldrin
• Endrin

References

1. ^ Jubb, A. H. (1975). Basic Organic Chemistry, Part 5 Industrial products. London: Wiley. ISBN 0-471-85014-4. 

• S. Kegley, B. Hill, S. Orme, PAN Pesticide Database, Pesticide Action Network, North America (San Francisco, CA. 2007), http://www.pesticideinfo.org

External links

• Dieldrin linked to earlier onset of Parkinson's disease