Fenbuconazole

Structural formula
	Structural formula without stereochemistry
General
Surname	Fenbuconazole
other names	( RS ) -4- (4-Chlorophenyl) -2-phenyl-2 - ((1 H -1,2,4-triazol-1-yl) methyl) butanenitrile; (±) -4- (4-Chlorophenyl) -2-phenyl-2 - ((1 H -1,2,4-triazol-1-yl) methyl) butanenitrile; ( RS ) -4- (4-chlorophenyl) -2-phenyl-2 - ((1 H -1,2,4-triazol-1-yl) methyl) butyric acid nitrile; (±) -4- (4-Chlorophenyl) -2-phenyl-2 - ((1 H -1,2,4-triazol-1-yl) methyl) butyric acid nitrile;
Molecular formula	C 19 H 17 ClN 4
Brief description	white solid
External identifiers / databases
EC number	406-140-2
ECHA InfoCard	100.100.769
PubChem	86138
Wikidata	Q3068332
properties
Molar mass	336.82 g mol −1
Physical state	firmly
density	1.28 g cm −3
Melting point	124-126 ° C
Vapor pressure	0.034 mPa (25 ° C)
solubility	almost insoluble in water, moderately soluble in n-heptane, readily soluble in ethyl acetate, acetone, xylene
safety instructions
GHS hazard labeling from Regulation (EC) No. 1272/2008 (CLP) , expanded if necessary Caution
H and P phrases	H: 410
	P: 273-501
Toxicological data	> 2000 mg kg −1 ( LD 50 , rat , oral ) ; > 5000 mg kg −1 ( LD 50 , rat , transdermal ) ;
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Fenbuconazole is a mixture of two isomeric chemical compounds from the group of triazoles and nitriles .

Extraction and presentation

Fenbuconazole can start with a phenylethylation of phenylacetonitrile z. B. obtained by 1- (2-bromoethyl) -4-chlorobenzene . A second alkylation on the same carbon atom with dibromomethane yields a compound with a reactive bromomethyl group. Fenbuconazole as a mixture of enantiomers can then be obtained by nucleophilic substitution of the halogen by triazolyl sodium .

Stereochemistry

Fenbuconazole has a stereocenter and accordingly forms two enantiomers . A 1: 1 mixture ( racemate ) of the ( S ) and ( R ) enantiomers is used:

Fenbuconazole enantiomers

properties

Fenbuconazole is a white solid that is insoluble in water. The compound is stable to hydrolysis and exposure to light. The half-life in aqueous suspension is 3.4 days. The technical product consists of a mixture of enantiomers.

use

Apple scab ( Venturia inaequalis )

Fenbuconazole is a triazole fungicide used in agriculture and horticulture. It is effective against leaf spot disease , yellow rust and brown rust in wheat , powdery mildew and net spot disease on wheat and barley, and scab and powdery mildew on apples and pears.

Admission

After withdrawing the application for approval, the EU Commission decided in 2008 not to include fenbuconazole in Annex I of Directive 91/414 / EEC. After a renewed application, the substance was added to the list of permissible active ingredients in plant protection products for use as a fungicide with effect from May 1, 2011.

In Germany, Austria and Switzerland, pesticide products containing this active ingredient are no longer approved.

Individual evidence

↑ ^a ^b ^c ^d data sheet fenbuconazole from Sigma-Aldrich , accessed on May 20, 2017 ( PDF ).
↑ ^a ^b ^c ^d ^e ^f Müller, F .; Ackermann, P .; Margot, P .: Fungicides, Agricultural, 2. Individual Fungicides in Ullmanns Enzyklopädie der Technischen Chemie , 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim, doi : 10.1002 / 14356007.o12_o06 .
↑ ^a ^b ^c Entry for CAS no. 114369-43-6 in the GESTIS substance database of the IFA , accessed on April 17, 2013(JavaScript required) .
↑ Entry on 4- (4-chlorophenyl) -2-phenyl-2 - [(1H-1,2,4-triazol-1-yl) methyl] butanenitrile Template: Linktext-Check / Escaped 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 .
^ ^A ^b Ulrich Schirmer, Peter Jeschke, Matthias Witschel: Modern Crop Protection Compounds: Herbicides . John Wiley & Sons, 2012, ISBN 978-3-527-32965-6 , pp. 779 ( limited preview in Google Book search).
↑ Elim M. Ulrich, Candice M. Morrison, Michael M. Goldsmith, William T. Foremann: Chiral Pesticides: Identification, Description, and Environmental Implications . In: Reviews of Environmental Contaminations and Toxicology. Springer 2012, Boston, Volume 217, pp. 1–74, DOI: 10.1007 / 978-1-4014-2329-4 1 , see p. 10.
↑ Implementing Regulation (EU) No. 540/2011 of the Commission of May 25, 2011 for the implementation of Regulation (EC) No. 1107/2009 of the European Parliament and of the Council with regard to the list of approved active substances , accessed on January 13, 2018 , p. 158.
↑ 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. 1043 ( limited preview in Google Book search).
↑ FAO: Fenbuconazole ,
↑ Directive 2010/87 / EU of the Commission of December 3, 2010 amending Council Directive 91/414 / EEC to include the active substance fenbuconazole and amending Decision 2008/934 / EC .
↑ General Directorate Health and Food Safety of the European Commission: Entry on Fenbuconazole in the EU pesticide database; Entry in the national registers of plant protection products in Switzerland , Austria and Germany ; accessed on December 7, 2019.

[Sigma-1] ta sheet fenbuconazole from Sigma-Aldrich , accessed on May 20, 2017 ( PDF ).

[Ullmann-2] ↑ ^a ^b ^c ^d ^e ^f Müller, F .; Ackermann, P .; Margot, P .: Fungicides, Agricultural, 2. Individual Fungicides in Ullmanns Enzyklopädie der Technischen Chemie , 2012 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim, doi : 10.1002 / 14356007.o12_o06 .

[GESTIS-3] Entry for CAS no. 114369-43-6 in the GESTIS substance database of the IFA , accessed on April 17, 2013(JavaScript required) .

[CLP_100.100.769-4] Entry on 4- (4-chlorophenyl) -2-phenyl-2 - [(1H-1,2,4-triazol-1-yl) methyl] butanenitrile Template: Linktext-Check / Escaped 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 .

[Ulrich_Schirmer,_Peter_Jeschke,_Matthias_Witschel-5] A ^b Ulrich Schirmer, Peter Jeschke, Matthias Witschel: Modern Crop Protection Compounds: Herbicides . John Wiley & Sons, 2012, ISBN 978-3-527-32965-6 , pp. 779 ( limited preview in Google Book search).

[Ulrich-6] Elim M. Ulrich, Candice M. Morrison, Michael M. Goldsmith, William T. Foremann: Chiral Pesticides: Identification, Description, and Environmental Implications . In: Reviews of Environmental Contaminations and Toxicology. Springer 2012, Boston, Volume 217, pp. 1–74, DOI: 10.1007 / 978-1-4014-2329-4 1 , see p. 10.

[VERORDNUNG-7] Implementing Regulation (EU) No. 540/2011 of the Commission of May 25, 2011 for the implementation of Regulation (EC) No. 1107/2009 of the European Parliament and of the Council with regard to the list of approved active substances , accessed on January 13, 2018 , p. 158.

[Terry_R._Roberts,_David_H._Hutson,_Philip_W._Lee,_Peter_H._Nicholls-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. 1043 ( limited preview in Google Book search).

[FAO-9] FAO: Fenbuconazole ,

[10] Directive 2010/87 / EU of the Commission of December 3, 2010 amending Council Directive 91/414 / EEC to include the active substance fenbuconazole and amending Decision 2008/934 / EC .

[PSM-11] General Directorate Health and Food Safety of the European Commission: Entry on Fenbuconazole in the EU pesticide database; Entry in the national registers of plant protection products in Switzerland , Austria and Germany ; accessed on December 7, 2019.