Bifenthrin

• (1R *, 3R * ) -3 - ( 2-chloro- 3 ,3,3- trifluoro-1 -propenyl) -2,2- dimethylcyclopropancarboxylsäure (2- methylbiphenyl -3-yl ) methyl ester
• Brigade
• Talstar

• 82657-04-3
• 439680-76-9 [ (1R, 3R )-form ]
• 439680-77-0 [( 1S, ​​3S )-form ]

White powder

Fixed

1.212 g · cm -3

51-66 ° C

285 ° C ( decomposition)

<1 hPa ( 25 ° C)

• Slightly soluble in water
• Soluble in most organic solvents

Risk

• 54.5 mg · kg -1 ( LD50, rat, oral)
• > 2000 mg · kg -1 ( LD50, Rabbit, transdermal)

Template: Infobox chemical / molecular formula search available

Bifenthrin is a chemical compound from the group of pyrethroids.

Production and representation

Bifenthrin can be prepared by reaction of triethyl 3 -methyl-2 -buten-1 -ol, 1,1,1 -trichloro- 2 ,2,2-trifluoroethane, potassium tert-butoxide, thionyl chloride and 2-methyl -3- hydroxymethyl be obtained biphenyl.

Properties

Physical Properties

Bifenthrin is a white solid which is slightly soluble in water. It is relatively stable to light and hydrolysis in the pH range 5 to 9

Chemical Properties

The double bond in the bifenthrin is always Z configuration, with respect to the absolute configuration of the two stereocenters at C- 1 and C- 3, the definitions differences in the literature. The CAS number 82657-04-3 refers to a 1:1 mixture of the (1R, 3R ) - and ( 1S, ​​3S)- isomers, in the literature but is also a 97:3 mixture ( cis: trans-) designated by the name of bifenthrin.

The 1S -cis- bifenthrin is 3 - to 4- times more toxic for humans as 1R -cis bifenthrin, while the latter is more than 300 times more effective as a pesticide.

Use

Bifenthrin is used as a pesticide. The effect is based on inhibition of the nerve signal transduction by Beeinflussing of sodium channels.

Bifenthrin was first approved in the U.S. in 1989 as an insecticide. In the EU, it was not included Council Directive 91/414/EEC of 2009 in the Annex I of the Directive and withdraw the authorization by 30 May 2011. Foundation was not acceptable in terms of ecotoxicology risk to aquatic vertebrates and uncertainty about the implications of the bioaccumulation in fish of the active ingredient. Further, showed high risks to mammals.

After requesting submission of further studies, which could alter the objections to the admission, bifenthrin was finally approved with effect from August 1, 2012 in the EU as a pesticide active ingredient. Supplier of bifenthrin, FMC Corporation.

In Germany and Austria are not, in Switzerland a plant protection product ( Talstar SC ) is authorized with this active ingredient.