Bifenthrin

Structural formula
Structural formula of an enantiomer of the cis form of racemic bifenthrin (see section chemical properties )
General
Surname	Bifenthrin
other names	(1 R * , 3 R * ) -3- (2-Chloro-3,3,3-trifluoro-1-propenyl) -2,2-dimethylcyclopropanecarboxylic acid (2-methylbiphenyl-3-yl) methyl ester brigade Talstar
Molecular formula	C 23 H 22 ClF 3 O 2
Brief description	White dust
External identifiers / databases
CAS number 82657-04-3 439680-76-9 [(1 R , 3 R ) form] 439680-77-0 [(1 S , 3 S ) form] EC number 617-373-6 ECHA InfoCard 100.120.070 PubChem 10938769 Wikidata Q415150
properties
Molar mass	422.87 g mol −1
Physical state	firmly
density	1.212 g cm −3
Melting point	51-66 ° C
boiling point	285 ° C (decomposition)
Vapor pressure	<1 hPa (25 ° C)
solubility	slightly soluble in water soluble in most organic solvents
safety instructions
GHS hazard labeling from  Regulation (EC) No. 1272/2008 (CLP) , expanded if necessary danger H and P phrases H: 351-331-300-372-317-410 P: 261-264-273-280-301 + 310-311
Toxicological data	54.5 mg kg −1 ( LD 50 ,  rat ,  oral ) > 2000 mg kg −1 ( LD 50 ,  rabbit ,  transdermal )
As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Bifenthrin is a chemical compound from the group of pyrethroids .

Extraction and presentation

Bifenthrin can be obtained by reacting triethyl orthoacetate ( triethyl orthoacetate ) with 3-methyl-2-buten-1-ol , 1,1,1-trichloro-2,2,2-trifluoroethane , potassium tert -butoxide , thionyl chloride and 2-methyl 3-hydroxymethyl-biphenyl can be obtained.

properties

Physical Properties

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

Chemical properties

The double bond in bifenthrin is always ( Z ) -configured, with regard to the absolute configuration of the two stereocenters at C-1 and C-3, the definitions in the literature differ. The CAS number 82657-04-3 refers to a 1: 1 mixture of the (1 R , 3 R ) and (1 S , 3 S ) isomers, but the literature also uses a 97: 3 mixture ( cis  : trans ) called Bifenthrin.

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

use

Bifenthrin is used as a plant protection product. The effect is based on the inhibition of nerve signal transmission by influencing the sodium channels.

Admission

Bifenthrin was first approved as an insecticide in the United States in 1989 . In the EU, it was not included in Annex I of Council Directive 91/414 / EEC in 2009 and approval was revoked by 30 May 2011 at the latest. The reason was an unacceptable ecotoxicological risk to aquatic vertebrates and the uncertainty about the effects of the bioaccumulation of the active substance found in fish . There were also high risks for mammals.

After the applicant had submitted further studies that could allay the concerns about the approval, Bifenthrin was finally approved in the EU as an active ingredient in plant protection products with effect from August 1, 2012 . Bifenthrin is supplied by FMC Corporation and Biesterfeld .

In Germany and Austria there are none, in Switzerland a plant protection product (Talstar SC) with this active ingredient is approved.

Individual evidence

1. ↑ ^{a b c d e f g h i} data sheet Bifenthrin, PESTANAL at Sigma-Aldrich , accessed on May 19, 2017 ( PDF ).
2. ↑ ^{a b c} ECHA: Background document to the Opinion proposing harmonized classification and labeling at Community level of bifenthrin , May 24, 2011.
3. ^ ^{A b c} Robert Irving Krieger: Handbook of Pesticide Toxicology . Academic Press, 2001, ISBN 0-12-426260-0 , pp. 1264 .
4. ↑ Entry on bifenthrin in the GESTIS substance database of the IFA , accessed on July 23, 2016(JavaScript required) .
5. ↑ entry on bifenthrin (ISO); (2-methylbiphenyl-3-yl) methyl rel- (1R, 3R) -3 - [(1Z) -2-chloro-3,3,3-trifluoroprop-1-en-1-yl] -2,2- dimethylcyclopropanecarboxylate in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on August 1, 2016. Manufacturers or distributors can expand the harmonized classification and labeling .
6. ↑ Thomas A. Unger: Pesticide Synthesis Handbook . William Andrew, 1996, ISBN 0-8155-1853-6 , pp. 932 ( limited preview in Google Book search).
7. ↑ Huigang Liu, Meirong Zhao, Cong Zhang, Yun Ma, Weiping Liu: Enantioselective cytotoxicity of the insecticide bifenthrin on a human amnion epithelial (FL) cell line. In: Toxicology. 253, 2008, pp. 89-96, doi: 10.1016 / j.tox.2008.08.015 .
8. ↑ Terry R. Roberts, David H. Hutson, Philip W. Lee, Peter H. Nicholls: Metabolic Pathways of Agrochemicals: Part 2: Insecticides and Fungicides . Royal Society of Chemistry, 1999, ISBN 0-85404-499-X , pp. 595 ( limited preview in Google Book search).
9. ↑ EPA: Bifenthrin Summary Document Registration Review: Initial Docket June 2010 ( Memento of April 12, 2013 in the Internet Archive ).
10. ↑ EU: Commission decision of November 30, 2009 on the non-inclusion of bifenthrin in Annex I of Council Directive 91/414 / EEC and the revocation of the authorizations for plant protection products with this active substance (PDF) (2009/887 / EC).
11. ↑ Implementing Regulation (EU) No. 582/2012 of the Commission of July 2, 2012 for the approval of the active ingredient bifenthrin according to Regulation (EC) No. 1107/2009 ... (PDF)
12. ↑ Press release FMC Corporation: Insecticide Bifenthrin from FMC Corporation approved again in Europe .
13. ^ Biesterfeld AG: Bifenthrin | Biesterfeld AG , accessed on November 11, 2019.
14. ↑ General Directorate Health and Food Safety of the European Commission: Entry on Bifenthrin in the EU pesticide database; Entry in the national registers of plant protection products in Switzerland , Austria and Germany ; accessed on March 13, 2016.