Penconazole

Structural formula
	Structural formula without stereochemistry
General
Surname	Penconazole
other names	(±) -1- [2- (2,4-dichlorophenyl) pentyl] -1 H -1,2,4-triazole; ( RS ) -1- [2- (2,4-dichlorophenyl) pentyl] -1 H -1,2,4-triazole; topaz;
Molecular formula	C 13 H 15 Cl 2 N 3
Brief description	white solid
External identifiers / databases
EC number	266-275-6
ECHA InfoCard	100.060.231
PubChem	91693
Wikidata	Q2426626
properties
Molar mass	284.18 g mol −1
Physical state	firmly
density	1.28 g cm −3
Melting point	60 ° C
Vapor pressure	3.66 10 −4 Pa (25 ° C)
solubility	practically insoluble in water (73 mg l −1 at 20 ° C)
safety instructions
H and P phrases	H: 302-361d-410
	P: 201-273-301 + 312-330-308 + 313-391-501
Toxicological data	2125 mg kg −1 ( LD 50 , rat , oral )
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Penconazole is a chemical compound from the triazole group . It is chiral and is used as a 1: 1 mixture of the mutually enantiomeric ( R ) form and the ( S ) form. It has been marketed by Ciba-Geigy as a pesticide ( fungicide ) since 1986 .

Extraction and presentation

Penconazole can be obtained from 2,4-dichlorobenzyl bromide. This reacts with potassium cyanate to form 2,4-dichlorophenylacetonitrile . Further reactions with sulfuric acid , 1-bromopropane , sodium borohydride , methanesulfonyl chloride and 1,2,4-triazole finally produce the end product.

Stereochemistry

Penconazole contains a stereocenter and consists of two enantiomers . This is a racemate , i.e. a 1: 1 mixture of ( R ) - and ( S ) -form:

Enantiomers of penconazole
( S ) -penconazole	( R ) -penconazole

use

Penconazole is used as a systemic azole fungicide with a protective and curative effect against powdery mildew in viticulture, pumpkin, pome fruit, ornamentals and vegetables.

Admission

In a number of EU countries, including Germany and Austria, as well as Switzerland, plant protection products containing this active ingredient are approved.

Individual evidence

↑ ^a ^b ^c Conclusion regarding the peer review of the pesticide risk assessment of the active substance penconazole . In: EFSA Journal . tape 6 , no. 10 , 2008, ISSN 1831-4732 , p. 175r , doi : 10.2903 / j.efsa.2008.175r .

↑ Penconazole data sheet from Sigma-Aldrich , accessed on May 20, 2017 ( PDF ).

↑ Entry on Penconazole in the Pesticide Properties DataBase (PPDB) of the University of Hertfordshire , accessed on April 2, 2020.

↑ ^a ^b ^c ^d Entry on penconazole. In: Römpp Online . Georg Thieme Verlag, accessed on November 15, 2014.

↑ ^a ^b ^c Entry on penconazole in the GESTIS substance database of the IFA , accessed on February 1, 2016(JavaScript required) .

↑ Entry on 1- [2- (2,4-dichlorophenyl) pentyl] -1H-1,2,4-triazole in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA), accessed on August 1, 2016. Manufacturer or distributor can expand the harmonized classification and labeling .

↑ Thomas A. Unger: Pesticide Synthesis Handbook . William Andrew, 1996, ISBN 0-8155-1853-6 , pp. 715 ( limited preview in Google Book search).

↑ ^a ^b Directorate-General for Health and Food Safety of the European Commission: Entry on penconazole in the EU pesticide database; Entry in the national registers of plant protection products in Switzerland , Austria and Germany ; accessed on March 25, 2016.

[EFSA-1] Conclusion regarding the peer review of the pesticide risk assessment of the active substance penconazole . In: EFSA Journal . tape 6 , no. 10 , 2008, ISSN 1831-4732 , p. 175r , doi : 10.2903 / j.efsa.2008.175r .